Patent Publication Number: US-2020298757-A1

Title: Staged troubleshooting and repair of vehicle trailer lighting malfunctions

Description:
TECHNICAL FIELD 
     The subject matter described herein relates generally to enabling vehicles to guide users through step-by-step troubleshooting and repair of apparently malfunctioning vehicle trailer tail lights. This method has particular but not exclusive utility for consumer and commercial vehicles, including cars and trucks. 
     BACKGROUND 
     Modern vehicles include complex electronic and electromechanical accessories, components, and subsystems, including power seats, seatbelts, sunroofs, sun shades, running boards, fold-out mirrors, mirror heaters, and others, leading to complex wiring assemblies and multiple opportunities for electronic issues (shorts, ground loops, firmware hang states, etc.). Even relatively simple systems such as trailer tail light assemblies may be routed through a complex system of wiring and logic circuits that make troubleshooting difficult for end users. 
     Troubleshooting a vehicle electrical component such as trailer tail lights (e.g., for failing to illuminate, or illuminating in the wrong sequence) can be a complex task with many unknowns, that could be the result of any of a number of possible causes. Further, tasks as seemingly simple as checking a fuse may be quite daunting, as many modern vehicles have three or more fuse boxes located throughout the vehicle (e.g., engine compartment, under the instrument panel, next to the driver seat, inside the instrument panel, behind the glove box, next to the battery, in the trunk, etc.). Then, after identifying the correct fuse and the correct fuse box location, a user often has to dismantle various vehicle components to access the fuse box and use a specialty tool to replace the fuse. Even after this is done, the problem may still persist. The user may then have to take the vehicle to a service station, despite an investment of substantial time and effort attempting to correct the problem at home. 
     For these and other reasons, current user&#39;s owner-accessible diagnostic and repair methods present numerous unaddressed challenges in the art. Accordingly, long-felt needs exist for diagnostic and repair systems that address the forgoing or other concerns. 
     The information included in this Background section of the specification is included for technical reference purposes only and is not to be regarded as subject matter by which the scope of the disclosure is to be bound. 
     SUMMARY 
     Disclosed are apparatus, systems, and methods for enabling vehicles to instruct users to perform staged, step-by-step troubleshooting and repair of apparently malfunctioning trailer lighting components, the apparatus, systems, and methods henceforth referred to collectively as a “trailer lighting diagnostic system.” The trailer lighting diagnostic system may detect faults and recommend specific actions to the user or vehicle owner, in order to isolate (and in some instances, repair) the fault. 
     One general aspect includes a vehicle including an automotive trailer lighting diagnostic system, the system including: a trailer, one or more trailer lights disposed on the trailer, one or more components of the vehicle or trailer that are associated with the one or more trailer lights, a user interface, and a control unit configured to activate the one or more trailer lights in a particular sequence, receive a signal identifying at least one malfunctioning trailer light of the one or more trailer lights, automatically identify a diagnostic procedure for the at least one malfunctioning trailer light from a plurality of diagnostic procedures and initiate the identified diagnostic procedure, execute the steps of the diagnostic procedure by: soliciting information from a user via the user interface, issuing instructions to the user via the user interface, executing branching logic steps, and initiate repair or replacement of the at least one malfunctioning trailer light through user actions via the user interface; and recommend service options to the user if the diagnostic procedure is unable to return the at least one malfunctioning trailer light to working order. 
     A system of one or more control units can be configured to perform particular operations or actions by virtue of having software, firmware, hardware, diagnostic procedures, fault trees, or a combination of them installed on the system that in operation causes or cause the system to perform the actions. One or more diagnostic procedures can be configured to perform particular operations or actions by virtue of including instructions that, when executed by data processing apparatus, cause the apparatus to perform the actions. Other embodiments of this aspect include corresponding control units, apparatus, and diagnostic procedures recorded on one or more control-unit-accessible storage devices, each configured to perform the actions of the methods. 
     Implementations may include one or more of the following features. The vehicle where soliciting information from the user or issuing instructions to the user involves a voice interface. The vehicle where soliciting information from the user or issuing instructions to the user involves a visual interface. The vehicle where soliciting information from the user or issuing instructions to the user involves a dashboard head unit. The vehicle where soliciting information from the user or issuing instructions to the user involves a portable device. The vehicle where the portable device includes an augmented reality device and the instructions to the user include augmented reality instructions. The vehicle where the at least one malfunctioning trailer light includes a brake light. The vehicle where the at least one malfunctioning trailer light includes a turn signal indicator light. The vehicle where the at least one malfunctioning trailer light includes a tail light. The vehicle where the at least one malfunctioning trailer light includes a backup light. The vehicle where the instructions to the user include activating controls within the automotive trailer lighting diagnostic system. The vehicle where the instructions to the user include physical examination of the one or more components of the vehicle or trailer that are associated with the one or more trailer lights. The vehicle where the instructions to the user include physical replacement of the one or more components of the vehicle or trailer that are associated with the one or more trailer lights. Implementations of the described techniques may include hardware, a method or process, or control unit software on a control-unit-accessible medium. 
     One general aspect includes a method for returning malfunctioning automotive trailer lamps to working condition, the method including: activating one or more trailer lamps in a sequence, receiving a status of at least one malfunctioning trailer lamp of the one or more trailer lamps by receiving a signal from a user via a user interface, identifying a diagnostic procedure stored in a memory from a plurality of diagnostic procedures stored in the memory, executing branching logic steps of the identified diagnostic procedure from the memory for the at least one malfunctioning trailer lamp; soliciting information from the user about the at least one malfunctioning trailer lamp, issuing instructions to the user regarding the at least one malfunctioning trailer lamp and, if at an endpoint of the diagnostic procedure, the at least one malfunctioning trailer lamp continues to malfunction, recommending service options to the user. Other embodiments of this aspect include corresponding control units, systems, apparatus, and instructions recorded on one or more control-unit-accessible storage devices, each configured to perform the actions of the methods. 
     Implementations may include one or more of the following features. The method where soliciting information from or issuing instructions to the user involves a voice interface. The method where soliciting information from the user or issuing instructions to the user involves a visual interface. The method where soliciting information from the user or issuing instructions to the user involves a dashboard head unit or portable device. The method where the portable device includes an augmented reality device. The method where the at least one malfunctioning trailer lamp includes a brake lamp, a turn signal lamp, a tail lamp, or a backup lamp. Implementations of the described techniques may include hardware, a method or process, or control unit instructions on a control-unit-accessible medium. 
     One general aspect includes a vehicle trailer lighting diagnostic module including a user interface, and a processor configured to activate one or more trailer lights of a vehicle in a particular sequence, receive a signal indicative of a status of one or more malfunctioning trailer lights of the one or more trailer lights, automatically identify a diagnostic procedure for the one or more malfunctioning trailer lights from a plurality of diagnostic procedures, and initiate the identified diagnostic procedure. The processor is also configured to execute branched logic paths of the identified diagnostic procedure, solicit information from a user regarding the one or more malfunctioning trailer lights, issue instructions to the user regarding the one or more malfunctioning trailer lights, and recommend service options to the user if an endpoint of the identified diagnostic procedure indicates a continued malfunction status of at least one of the one or more malfunctioning trailer lights. Other embodiments of this aspect include corresponding control units, apparatus, and diagnostic procedures or fault trees recorded on one or more control-unit-accessible storage devices, each configured to perform the actions of the methods. The trailer lighting diagnostic system disclosed herein has particular, but not exclusive, utility for consumer and commercial vehicles, including cars and trucks. 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. A more extensive presentation of features, details, utilities, and advantages of the method, as defined in the claims, is provided in the following written description of various embodiments of the disclosure and illustrated in the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Illustrative embodiments of the present disclosure will be described with reference to the accompanying drawings, of which: 
         FIG. 1  is a diagrammatic illustration of a vehicle including a trailer lighting diagnostic system, in accordance with at least one embodiment of the present disclosure. 
         FIG. 2  is a block diagram including several components of the trailer lighting diagnostic system of  FIG. 1 , in accordance with at least one embodiment of the present disclosure. 
         FIG. 3  is a diagrammatic illustration of an example vehicle including trailer and trailer lighting, in accordance with at least one embodiment of the present disclosure. 
         FIG. 4  is a flow diagram showing exemplary process steps undertaken by a trailer lighting diagnostic system according to at least one embodiment of the present disclosure. 
         FIG. 5  is a diagrammatic illustration of an example user interrogation display according to at least one embodiment of the present disclosure. 
         FIG. 6  is a diagrammatic view of an example augmented reality display on a portable device in accordance with at least one embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It is nevertheless understood that no limitation to the scope of the disclosure is intended. Any alterations and further modifications to the described devices, systems, and methods, and any further application of the principles of the present disclosure are fully contemplated and included within the present disclosure as would normally occur to one skilled in the art to which the disclosure relates. It is fully contemplated that the features, components, and/or steps described with respect to one embodiment may be combined with the features, components, and/or steps described with respect to other embodiments of the present disclosure. For the sake of brevity, however, the numerous iterations of these combinations will not be described separately. 
     Often, when diagnosing faults in automotive accessories, components, or subsystems, vehicle owners are unaware of the possible causes or the steps required to isolate them. The trailer lighting diagnostic system of the present disclosure may provide a simple, convenient, and cost-effective method to aid a user in troubleshooting problems that occur with vehicle trailer lights (e.g., brake lights, turn signals). In some embodiments, the trailer lighting diagnostic system begins troubleshooting the problem by asking a series of questions, starting with questions relating to the most likely or most easily identifiable cause down to the most complex issues that may require a service technician. In some embodiments, the trailer lighting diagnostic system provides instructions through a user interface such as an interactive voice interface, touchscreen, or both where instructions may be given through any combination of audio, visual (e.g., images, text, symbols), or video playback methods, including streaming from an onboard database, or through a wireless network or server connection, or cloud storage device. 
     In some exemplary embodiments, an application program interface (API) on a smartphone, onboard monitor, or other electronic device may be employed. The trailer lighting diagnostic system may provide a branched diagnostic procedure that walks a user through one or more steps to inspect for symptoms (to further diagnose the problem) or one or more steps to repair the problem. After each step, the system will ask the user to confirm whether the issue was resolved or whether a specific action has occurred (e.g., whether a lamp is illuminated). In an example, once positive or negative confirmation is given, the system will complete the troubleshooting or move to a next possible cause and remedy until the issue is resolved. This will help the user isolate the issue, and for each point of occurrence, if resolution criteria are not met, the system may provide locations for parts to be replaced, instructions on how to replace them, and the ability to check part inventory at nearby dealerships. Some issues may require service with sophisticated equipment by a professional technician, and in these cases, the trailer lighting diagnostic system may identify that such service is necessary and recommend it to the user. 
     The present disclosure aids substantially in automotive component fault correction, by improving the ability of vehicles to overcome certain malfunctions in an automated manner, without the need for professional service or complex actions undertaken by a vehicle owner. Implemented on a processor in communication with a sensor associated with the malfunctioning component, the trailer lighting diagnostic system disclosed herein may provide practical self-diagnosis and self-repair capabilities to motor vehicles. This streamlined and augmented diagnostic and repair capability transforms a non-functioning vehicle component into a functioning one, without the normally routine need for a user to read manuals, follow written procedures, put the vehicle into a “manufacturer mode”, or be familiar with manufacturer-specific and model-specific fault trees. This unconventional approach improves the functioning and uptime of the vehicle while reducing cost of ownership, by automatically restoring malfunctioning vehicle components to working condition. 
     The trailer lighting diagnostic system may comprise a subroutine that includes a user interface viewable on a display, and operated by control processes executed on a processor that may accept user inputs from a user interface such as a voice, gesture, or touchscreen interface, and that is in communication with one or more trailer lights. In that regard, the control processes perform certain specific operations in response to different conditions, including but not limited to sensor readings and user inputs. Certain structures, functions, and operations of the processor, display, sensors, and user input systems are known in the art, while others are recited herein to enable novel features or aspects of the present disclosure with particularity. 
     These descriptions are provided for exemplary purposes, and should not be considered to limit the scope of the trailer lighting diagnostic system. Certain features may be added, removed, or modified without departing from the spirit of the claimed subject matter. 
       FIG. 1  is a diagrammatic illustration of a vehicle including a trailer lighting diagnostic system, in accordance with at least one embodiment of the present disclosure. In an example, the trailer lighting diagnostic system is referred to by the reference numeral  100  and includes a vehicle  105 , such as an automobile, and a vehicle control unit  110  located on the vehicle  105 . The vehicle  105  may include a front portion  115   a  (including a front bumper), a rear portion  115   b  (including a rear bumper), a right side portion  115   c  (including a right front quarter panel, a right front door, a right rear door, and a right rear quarter panel), a left side portion  115   d  (including a left front quarter panel, a left front door, a left rear door, and a left rear quarter panel), and wheels  115   e.  A communication module  120  is operably coupled to, and adapted to be in communication with, the vehicle control unit  110 . The communication module  120  is adapted to communicate wirelessly with a central server  125  via a network  130  (e.g., a 3G network, a 4G network, a 5G network, a Wi-Fi network, or the like). The central server  125  may provide information and services including but not limited to include location, mapping, scheduling, SMS, and email. 
     An operational equipment engine  140  is operably coupled to, and adapted to be in communication with, the vehicle control unit  110 . A sensor engine  150  is operably coupled to, and adapted to be in communication with, the vehicle control unit  110 . The sensor engine  150  is adapted to monitor various components of, for example, the operational equipment engine  140 , as will be described in further detail below. An interface engine  155  is operably coupled to, and adapted to be in communication with, the vehicle control unit  110 . In addition to, or instead of, being operably coupled to, and adapted to be in communication with, the vehicle control unit  110 , the communication module  120 , the operational equipment engine  140 , the sensor engine  150 , and/or the interface engine  155  may be operably coupled to, and adapted to be in communication with, another of the components via wired or wireless communication (e.g., via an in-vehicle network). In some examples, the vehicle control unit  110  is adapted to communicate with the communication module  120 , the operational equipment engine  140 , the sensor engine  150 , and the interface engine  155  to control at least partially the interaction of data with and between the various components of the trailer lighting diagnostic system  100 . 
     The term “engine” is meant herein to refer to an agent, instrument, or combination of either, or both, agents and instruments that may be associated to serve a purpose or accomplish a task—agents and instruments may include sensors, actuators, switches, relays, power plants, system wiring, computers, components of computers, programmable logic devices, microprocessors, software, software routines, software modules, communication equipment, networks, network services, and/or other elements and their equivalents that contribute to the purpose or task to be accomplished by the engine. Accordingly, some of the engines may be software modules or routines, while others of the engines may be hardware and/or equipment elements in communication with any or all of the vehicle control unit  110 , the communication module  120 , the network  130 , or a central server  125 . 
     In this example, the vehicle  105  also includes a chassis electronic control unit (ECU)  111  which controls elements of the vehicle&#39;s suspension system, a brake ECU  112  which controls the braking system or elements thereof, and a drive train ECU  113  (variously known as an engine ECU, power plant ECU, or motor ECU) that controls elements of the motor and drivetrain. A reader of ordinary skill in the art will understand that other components or arrangements of components may be found in a vehicle  105 , and that the same general principles apply to electric vehicles, internal combustion vehicles, and hybrid vehicles. 
     In some embodiments, the trailer lighting diagnostic system  100  further includes a Trailer Diagnostic Module (TDM)  182 . 
       FIG. 2  is a block diagram including several components of the trailer lighting diagnostic system of  FIG. 1 , in accordance with at least one embodiment of the present disclosure. It is worth noting that the components of the vehicle  105  may be located either permanently or temporarily as a part of the vehicle  105 . The vehicle control unit (VCU)  110  includes a processor  165  and a memory  170 . In some examples, the communication module  120 , which is operably coupled to, and adapted to be in communication with, the vehicle control unit  110 , includes a transmitter  175  and a receiver  180 . In some examples, one or the other of the transmitter  175  and the receiver  180  may be omitted according to the particular application for which the communication module  120  is to be used. In other examples, the transmitter  175  and receiver  180  are combined into a single transceiver that performs both transmitting and receiving functions. 
     In some examples, the operational equipment engine  140 , which is operably coupled to, and adapted to be in communication with, the vehicle control unit  110 , includes a plurality of devices configured to facilitate driving of the vehicle  105 . In this regard, the operational equipment engine  140  may be designed to exchange communication with the vehicle control unit  110 , so as to not only receive instructions, but to provide information on the operation of the operational equipment engine  140 . For example, the operational equipment engine  140  may include a vehicle battery  190 , a motor  195 , a drivetrain  200 , a steering system  205 , and a braking system  210 . In an example, the vehicle battery  190  provides electrical power to the motor  195  to drive the wheels  115   e  of the vehicle  105  via the drivetrain  200 . In some examples, in addition to providing power to the motor  195  to drive the wheels  115   e  of the vehicle  105  via the drivetrain  200 , the vehicle battery  190  provides electrical power to another component of the operational equipment engine  140 , the vehicle control unit  110 , the communication module  120 , the sensor engine  150 , the interface engine  155 , or any combination thereof. In some examples, the vehicle battery  190  includes a battery identification device  215 . The battery identification device  215  is adapted to communicate with one or more components of the sensor engine  150 , and stores data identifying the vehicle battery  190  such as, for example, manufacturing information (e.g., production date, production facility, etc.), battery characteristic(s) information, battery identification number information, electric vehicle compatibility information, or the like. 
     In some examples, the sensor engine  150 , which is operably coupled to, and adapted to be in communication with, the vehicle control unit  110 , includes devices such as sensors, meters, detectors, or other devices configured to measure or sense a parameter related to a driving operation or other operation of the vehicle  105 . For example, the sensor engine  150  may include a global positioning system  220 , a humidity sensor  225 , a temperature sensor  230 , a barometric pressure sensor  235 , a magnetic sensor  240 , a shock/vibration sensor  245 , a vehicle impact sensor  250 , an airbag sensor  255 , a braking sensor  260 , an accelerometer  265 , a speedometer  270 , a tachometer  275 , a battery load sensor  280 , a vehicle identification device  285 , a tire pressure monitoring system (TPMS)  114 , a weight sensor  116 , or any combination thereof. The sensors or other detection devices may be configured to sense or detect activity, conditions, and circumstances in an area to which the device has access, e.g., ambient conditions or conditions within a battery compartment. Sub-components of the sensor engine  150  may be deployed at any operational area where information on the driving of the vehicle  105  may occur. Readings from the sensor engine  150  are fed back to the vehicle control unit  110 . Stored and reported performance data may include the sensed data, or may be derived, calculated, or inferred from sensed data. The vehicle control unit  110  may send signals to the sensor engine  150  to adjust the calibration or operating parameters of the sensor engine  150  in accordance with a control program in the vehicle control unit  110 . The vehicle control unit  110  is adapted to receive and process performance data from the sensor engine  150  or from other suitable source(s), and to monitor, store (e.g., in the memory  170 ), and/or otherwise process (e.g., using the processor  165 ) the received performance data. 
     The braking sensor  260  is adapted to monitor usage of the vehicle  105 &#39;s braking system  210  (e.g., an antilock braking system  210 ) and to communicate the braking information to the vehicle control unit  110 . The accelerometer  265  is adapted to monitor acceleration of the vehicle  105  and to communicate the acceleration information to the vehicle control unit  110 . The accelerometer  265  may be, for example, a two-axis accelerometer  265  or a three-axis accelerometer  265 . In some examples, the accelerometer  265  is associated with an airbag of the vehicle  105  to trigger deployment of the airbag. The speedometer  270  is adapted to monitor speed of the vehicle  105  and to communicate the speed information to the vehicle control unit  110 . In some examples, the speedometer  270  is associated with a display unit of the vehicle  105  such as, for example, a display unit of the interface engine  155 , to provide a visual indication of vehicle speed to a driver of the vehicle  105 . The tachometer  275  is adapted to monitor the working speed (e.g., in revolutions-per-minute) of the vehicle  105 &#39;s motor  195  and to communicate the angular velocity information to the vehicle control unit  110 . In some examples, the tachometer  275  is associated with a display unit of the vehicle  105  such as, for example, a display unit of the interface engine  155 , to provide a visual indication of the motor  195 &#39;s working speed to the driver of the vehicle  105 . The battery load sensor  280  is adapted to monitor charging, discharging, and/or overcharging of the vehicle battery  190  and to communicate the charging, discharging, and/or overcharging information to the vehicle control unit  110 . 
     In some examples, the vehicle identification device  285  stores data identifying the vehicle  105  such as, for example, manufacturing information (e.g., make, model, production date, production facility, etc.), vehicle characteristic(s) information, vehicle identification number (“VIN”) information, battery compatibility information, or the like. The vehicle identification device  285  is adapted to communicate with the battery identification device  215  (or vice versa), as indicated by arrow  286 . In some examples, the vehicle identification device  285  and the battery identification device  215  may each communicate with the vehicle control unit  110 . 
     In some examples, the interface engine  155 , which is operably coupled to, and adapted to be in communication with, the vehicle control unit  110 , includes at least one input and output device or system that enables a user to interact with the vehicle control unit  110  and the functions that the vehicle control unit  110  provides. For example, the interface engine  155  may include a display unit  290  and an input/output (“I/O”) device  295 . The display unit  290  may be, include, or be part of multiple display units. In some examples, the display unit  290  may include one, or any combination, of a central display unit associated with a dash of the vehicle  105 , an instrument cluster display unit associated with an instrument cluster of the vehicle  105 , and/or a heads-up display unit associated with the dash and a windshield of the vehicle  105 ; accordingly, as used herein the reference numeral  290  may refer to one, or any combination, of the display units. The I/O device  295  may be, include, or be part of a communication port (e.g., a USB port), a Bluetooth communication interface, a tough-screen display unit, soft keys associated with a dash, a steering wheel, or another component of the vehicle  105 , and/or similar components. Other examples of sub-components that may be part of the interface engine  155  include, but are not limited to, audible alarms, visual alerts, telecommunications equipment, and computer-related components, peripherals, and systems. 
     In some examples, a portable user device  300  operated by an occupant of the vehicle  105  may be coupled to, and adapted to be in communication with, the interface engine  155 . For example, the portable user device  300  may be coupled to, and adapted to be in communication with, the interface engine  155  via the I/O device  295  (e.g., the USB port and/or the Bluetooth communication interface). In an example, the portable user device  300  is a handheld or otherwise portable device which is carried onto the vehicle  105  by a user who is a driver or a passenger on the vehicle  105 . In addition, or instead, the portable user device  300  may be removably connectable to the vehicle  105 , such as by temporarily attaching the portable user device  300  to the dash, a center console, a seatback, or another surface in the vehicle  105 . In another example, the portable user device  300  may be permanently installed in the vehicle  105 . In some examples, the portable user device  300  is, includes, or is part of one or more computing devices such as personal computers, personal digital assistants, cellular devices, mobile telephones, wireless devices, handheld devices, laptops, audio devices, tablet computers, game consoles, cameras, smartwatches, and/or any other suitable devices. In several examples, the portable user device  300  is a smartphone such as, for example, an iPhone® by Apple Incorporated. 
     In some embodiments, the trailer lighting diagnostic system  100  further includes a trailer diagnostic module (TDM)  182 . The TDM  182  may be a software module, a hardware module, a firmware module, or any combination thereof, and may be a standalone module or may be integrated into other vehicle components such as the VCU  110  or Sensor Engine  150 . In these embodiments, the TDM is in communication with vehicle trailer lighting (see  FIG. 3 ), either by receiving data from sensors associated with trailer lighting (e.g., fuse or lamp filament continuity sensors), by receiving data from status variables associated with each component (e.g., status bits, status bytes, status words, or error codes), or by exchanging other data with an ECU or VCU associated with the trailer lighting. 
     A reader of ordinary skill in the art will understand that other components or arrangements of components may be found in a vehicle  105 , and that the same general principles apply to electric vehicles, internal combustion vehicles, and hybrid vehicles. 
       FIG. 3  is a diagrammatic illustration of an example vehicle  105  including trailer  350  and trailer lighting  356 , in accordance with at least one embodiment of the present disclosure. 
     In the example shown in the figure, the vehicle  105  includes a towing diagnostic module or trailer diagnostic module  182 , trailer hitch  320 , vehicle-side trailer wiring harness  322 , and vehicle-side trailer wiring connector  324 . The trailer includes a trailer-side wiring connector  334 , trailer-side wiring harness  332 , hitch tongue  330 , trailer bed  340 , lamp wiring harness  352 , lamp assembly  356 , and lamp bulb  358 . In an example, the vehicle side wiring harness is in communication with at least one of the VCU  110 , sensor engine  150 , trailer diagnostic module (TDM)  182 , and connects to the trailer-side wiring harness  332  through the vehicle-side connector  324  and trailer-side connector  334 . In an example, the trailer wiring harness  332  is mated to the lamp wiring harness  352  underneath the trailer bed  340 , although other arrangements are possible. It is noted that a typical trailer will have at least two lamp assemblies  356 : one for the left tail light, turn signal, brake light, and backup light, and one for the right tail light, turn signal, and brake light, and backup light. Each lamp assembly  356  may have its own lamp wiring harness  352 , or a single lamp wiring harness  352  may control multiple lamp assemblies. 
     In some examples, the tail light, turn signal, and brake light are three different bulbs  358  which illuminate according to different stimuli. In other examples, two or more of the tail light, blinker light, and brake light functions may be displayed through different brightness levels of a single bulb  358 . Different brightness levels may be achieved through any combination of voltage changes, current changes, pulse width modulation, or other related methods. Illumination of the bulbs  358  may be controlled directly through wiring (e.g., activated by a brake pedal, blinker switch, or headlight switch), or may be controlled through software or firmware in an ECU  310  or VCU  110 . 
     In some instances, failures in trailer lighting may be mechanical in nature (e.g., a broken bulb  358  or lamp assembly  356 ), or electronic (e.g., a shorted ECU  310 ), or electrical (e.g., a blown fuse  316 , or a disconnected wire or misconnected wire in a wiring harness  322 ,  332 , or  352 ), in which case, physical replacement of the failed components may be the only way to restore the lighting to an operational state. In other instances, failure of the component may involve software or firmware in a safe mode, maintenance mode, or hang state. Failures may also involve failure of a hardware-based or software-based sensor  315  (e.g., a continuity sensor). Resetting the sensor  315 , ECU  310 , or VCU  110  may clear this error condition. Failures may also involve a fuse  316  that has blown, such that replacing the fuse  316  may correct the malfunction. 
     In some embodiments, the trailer lighting diagnostic system receives an input from the user via the user interface (e.g. via voice, virtual agent, or touch input operating for example on the interface engine  155  or portable device  300 ), which identifies a problem. If more information is required, the system may ask questions of the user or ask the user to perform specific tasks (e.g., actuating a switch, or verifying the position, movement, or other state of a vehicle component) until the provided information describes or isolates the problem sufficiently that the system has identified a probable root cause and probable corrective action, and then verified that the corrective action has succeeded. In some instances, if the system is not able to resolve the problem, it may help further isolate a root cause of the problem and thus narrow the list of possible remedies. In some embodiments, the trailer lighting diagnostic system asks the user to confirm whether a trailer lamp is functioning properly. If not, the system will continue asking questions or recommending actions relating to the diagnosis. In other embodiments, the system automatically detects whether the component is working (e.g., by reading a continuity sensor). 
     The process continues until the problem is resolved. In instances where the root cause of a problem cannot be completely resolved by the user, the trailer lighting diagnostic system may recommend service options to the user for having the vehicle professionally serviced. 
     The trailer lighting diagnostic system of the present disclosure may provide a simple, convenient, and cost-effective method to aid in the resolution of problems that occur when trailer lights cease to function, or function incorrectly. In some embodiments, the trailer lighting diagnostic system begins troubleshooting the problem by asking a series of questions. This may start with questions directly relating to the onset of the problem. In other instances, the system begins troubleshooting by reading sensor values internal to the vehicle. If the answers suggest that a system reset or re-calibration will be helpful, either in resolving the issue or in further isolating a fault, the trailer lighting diagnostic system may recommend the steps required to reset or re-calibrate one or more components of the vehicle. 
     In some instances, the trailer lighting diagnostic system may guide the user through calibration or reset of a sensor (e.g., a continuity sensor) that is part of a malfunctioning subsystem. In other instances, the trailer lighting diagnostic system may calibrate or reset an electronic control unit (ECU) that is part of or local to the malfunctioning component or subsystem. In still other instances, the trailer lighting diagnostic system may reset the entire vehicle (e.g., by resetting a Vehicle Control Unit or VCU  110 ). 
     In instances where user interaction through a user interface is employed, the user may provide problem descriptions and answer questions through voice interaction, touchscreen, or any combination of audio, visual, gesture, selectable image, or virtual agent interaction. In some embodiments, diagnostic procedures are selected from a plurality of diagnostic procedures stored in an onboard database, or in a remote database accessed through a wireless network, server connection, or cloud storage device. 
       FIG. 4  is a flow diagram showing exemplary process steps undertaken by the trailer lighting diagnostic system  100  according to at least one embodiment of the present disclosure. The diagnostic system or the method carried out by the diagnostic system employs branching logic steps to determine performance parameters related to a malfunctioning or apparently malfunctioning component (e.g., a trailer brake light) by interacting with the user via the user interface (e.g., the interface engine  155  or portable device  300 ), in order to isolate, diagnose, and if possible guide user actions (e.g., activating controls, or physical examination or replacement of subcomponents), to repair the root cause of the component malfunction (e.g., a blown fuse or an ECU in a safe mode or hang state). Some steps involve branching logic decisions made internal to the system  100 . Other steps require the user to visually observe a given lamp and answer questions about its behavior. Still other steps require the user to perform physical examination of vehicle or trailer subcomponents such as fuses  316 , connectors (e.g., connectors  324  and  334 ), bulbs  358 , and wiring harnesses (e.g., harnesses  322 ,  332 , and  352 ), as detailed below. Still other steps require physical replacement of the inspected components. 
     In an example, the method begins with step  402 , in which a lamp or bulb  358  is checked to see whether it is illuminating. The check at  402  may be performed either visually by a user or else autonomously by the trailer diagnostic module  182 . The method performed by the diagnostic system  100  then proceeds to step  404 , where either the trailer diagnostic module  182  determines whether the lamp or bulb  358  is illuminating at all, (e.g., by checking a continuity sensor), or the user interface (e.g., interface engine  155  or portable device  300 ) instructs the user to make this determination by visual inspection. When the user performs a visual inspection, the user may enter a response, such as yes (illuminating), or no (not illuminating) at the user interface. When automatically checked, the trailer diagnostic module  182  receives the response from the sensing component (e.g., continuity sensor). For clarity, these inputs (from the user or automatically from components of the diagnostic system) are not always reiterated through the example process described with reference to  FIG. 4 , yet they may be present whenever feedback is required. It is worth noting that the trailer diagnostic module  182  may perform the steps described via the user interface. Accordingly, user interface instructions may be based on processing of information and execution of the processes at the trailer diagnostic module  182 . 
     If the answer at  404  is no, the lamp or bulb  358  is not illuminating, execution branches to step  406 , where the user interface (under control of the trailer diagnostic module  182 ) instructs the user to determine whether the connectors (e.g., connectors  324  and  334 ) are connected. If the answer is input or automatically detected as no at  406 , execution branches to step  412 , which is a jump to step  450 , described below. If the answer is input or automatically detected as yes at  406  (i.e., the connectors are indeed connected), then execution branches to step  408  where the user interface instructs the user to determine whether the connector pins (e.g., pins  326 ) are straight, and correctly oriented within the connection. If the answer is no at  408  (i.e., the pins are not straight or not correctly oriented), execution again branches to step  412  based on the answers received at the trailer diagnostic module  182  (via user input or sensor input). 
     If the answer is input or automatically detected as yes at  408  (i.e., the pins are straight and correctly oriented), then execution branches to step  410 , where either the diagnostic module  182  determines whether there is a blown fuse (e.g., fuse  316 ) associated with that particular lamp or bulb, or the user interface (e.g., interface engine  155  or portable device  300 ) instructs the user to make the same determination. In some embodiments this step may be executed by, for example, instructing the user to remove and inspect a particular fuse at a particular location within the vehicle, and compare the fuse against representative images of an intact and a blown fuse. In other embodiments, the state of the fuse may be determined automatically, by, for example, checking the state of an electrical continuity sensor monitoring the fuse. If the answer at  410  is input or automatically detected as no (i.e., there is no blown fuse), then execution branches to step  414 , where the trailer diagnostic module  182  uses the user interface to instruct the user to determine whether there is a burned-out bulb  358 . The filament of an incandescent light bulb may be inspected in a manner similar to a fuse, as described above. An LED bulb can be tested in a bulb tester, or by connecting it to an appropriate DC power source and ground either within the vehicle or external to the vehicle Like fuses, bulbs may also be tested autonomously by the trailer diagnostic module  182  via a continuity sensor. If the answer at  414  is yes (i.e., the bulb  358  is burned out), execution branches to step  412 , which is a jump to step  450 , described below. 
     If the answer at  414  is no (i.e., the bulb is not burned out), then execution branches to step  416 , where the user interface (e.g., interface engine  155  or portable device  300 ) instructs the user to determine (by inspection or other methods) whether a wiring harness (e.g., wiring harness  322 ,  332 , or  352 ) is intact. In some embodiments, this determination may be made autonomously by the trailer diagnostic module  182  through continuity testing. If the answer at  416  is no (i.e., the harness is not intact), execution branches to step  412 , which is a jump to step  450 . If the answer at  416  is yes (i.e., the wiring harness is intact), then the problem may be suspected to be subtle or complex or inaccessible enough to require professional servicing of the vehicle. Execution therefore proceeds to endpoint step  418 , where professional servicing is recommended to the user via the user interface (e.g., the interface engine  155  or portable device  300 ). 
     If the answer at step  404  is yes, the lamp or bulb  358  is illuminating, then execution branches to step  420 , where the user interface instructs the user to determine (e.g., by visual inspection) whether the illumination of the bulb  358  is intermittent or dim. In some embodiments, this determination can instead be made autonomously by the TDU  182  using a continuity sensor. If the answer at  420  is yes (i.e., the illumination of the bulb is intermittent or dim), execution branches to step  422 . In step  422 , the user interface instructs the user to determine whether the connectors (e.g., connectors  424  and  434 ) are seated correctly. This may be done, for example, by asking the user (via the user interface) to disconnect and reconnect the connectors (e.g., connectors  324  and  334 ) several times. In some embodiments, a pictorial or video demonstration is provided to the user via the user interface (e.g., the interface engine  155  or portable device  300 ). If the answer at  422  is no (i.e., the connectors are not seated correctly), then execution branches to step  412 , which is a jump to step  450 . If the answer at  422  is yes, (i.e., the connectors are seated correctly), then execution branches to step  424 , wherein the user interface instructs the user to determine (e.g., by visual inspection) whether there is dirt, water, debris, or corrosion in any of the connectors (e.g., connectors  324  and  334 ). If the answer at  424  is yes (i.e., debris is present), then execution branches to step  412 . If the answer at  424  is no (i.e., debris is not present), then execution branches to step  426 , where it is noted to the user via the user interface that one or more wiring harnesses are wired incorrectly. Execution then proceeds to step  412 , which is a jump to step  450 . 
     If the answer to step  420  is no (i.e., the illumination of the lamp or bulb  358  is not intermittent or dim), then execution branches to step  428 , where the user interface (e.g., interface engine  155  or portable device  300 ) instructs the user to determine whether the lamp is operating in the correct sequence. For example, if the lamp is a right turn signal indicator, is it flashing when the right turn signal is activated? If the answer at  428  is yes (i.e., the lamp or bulb  358  is operating in the correct sequence), then execution branches to endpoint step  430 , where the user is informed that the lamp or bulb  358  is working correctly. If the at  428  answer is no (i.e., the lamp or bulb  358  is not illuminating in the correct sequence), then execution branches to step  432 , where the user interface instructs the user to determine whether the connectors (e.g., connectors  324  and  334 ) are aligned correctly. Some connectors have tabs, detents, or other features making it difficult for a user to connect them in the wrong orientation, but some connectors do not have these features, and some users may inadvertently or deliberately modify a connector such that an improperly aligned connection becomes more likely. Therefore, a user might be asked (via the user interface) to flip a connector over and see whether it fits, or to perform other related actions. If the answer at  432  is no (i.e., the connector is not aligned correctly), then execution branches to step  412 , which is a jump to step  450 . If the answer at  432  is yes (i.e., the connector is aligned correctly), then execution jumps to step  426 , described above. 
     In step  450 , the user is informed (via the user interface) that repair or replacement is needed for the subcomponent most recently interacted with. For example, if step  450  is reached from step  426 , then repair or replacement of a wiring harness is needed. If step  450  is reached from step  414 , then a bulb needs to be repaired or replaced. Execution then proceeds to step  452 , where the user is given instructions (via the user interface) for the repair or replacement of that particular subcomponent. In some instances (e.g., changing a bulb), these instructions may be brief and straightforward. In other instances (e.g., repair of a wiring harness), step  452  may be complex an may involve multiple substeps that are specific to that particular subcomponent, problem, vehicle type, or model year. Such substeps may for example be executed as a sub-process from within the system  100 . Once step  452  is complete, this means the repair or replacement of the appropriate subcomponent is believed to be complete. Execution then proceeds to step  454 , wherein the trailer diagnostic unit  182  activates all of the trailer lamps in a particular sequence. The system  100  then proceeds to step  456 , where the user is asked (via the user interface) whether the originally identified problem has been fixed, i.e., whether the lamp or bulb  358  in question now illuminates properly at the correct time in the sequence. If the answer at  456  is yes (i.e., the problem is fixed), the execution proceeds to endpoint step  460 , where the diagnostic and repair procedure is declared to be finished. If the answer at  456  is no (i.e., the problem is not fixed because the lamp or bulb  358  is not illuminating correctly, or not illuminating at the correct time in the sequence), then execution proceed to step  458 , which is a return to step  402  to re-start the diagnostic process. 
     These steps describe a particular diagnostic procedure of a particular embodiment of the trailer lighting diagnostic system  100  of the present disclosure. A reader of ordinary skill in the art will understand that the system  100  may employ diagnostic procedures comprising additional steps not described above, or may omit one or more of the described steps, or may perform one or more steps in a different sequence than described above, while remaining within the spirit, function, and advantages of the present disclosure. In particular, delay and trigger steps may be incorporated such that, for example, if an ECU  310  or VCU  110  is reset or restarted, the system  100  allows a certain interval to pass such that the ECU  310  or VCU  110  may enter a steady state before the system  100  proceeds to the next step. It is noted that some embodiments may include advantageous arrangements wherein user action is solicited only when autonomous interventions for a given problem have been attempted and have not been successful. 
     It is further noted that in some embodiments the system may include interfaces to mapping and scheduling functions external to the vehicle, such that when the system advises a user to have the vehicle professionally serviced, the system may be capable of identifying an appropriate service station (either autonomously or guided by user inputs), scheduling a service appointment that fits within the schedules of both the user and the service station, sending a detailed writeup of the problem to the service station (e.g., identity of the nonworking component and all steps taken to isolate, diagnose, or repair it.), and sending an automated calendar invitation to the user. Such embodiments are fully contemplated. 
     It is further noted that in some embodiments the trailer lighting diagnostic system  100  issues service instructions to the user through an augmented reality (AR) device providing AR instructions, wherein for example the locations of vehicle subcomponents (e.g., motors and relays), or the proper method for operating vehicle components (e.g., switches), or the proper methods for removing and replacing vehicle subcomponents (e.g., fuses) may be shown as virtual animation overlaid on top of live video. This may be done for example through the screen of a portable device  300  such as a smartphone, tablet, or AR-capable headset. 
       FIG. 5  is a diagrammatic illustration of an example user interrogation display or Human Machine Interface (HMI)  500  according to at least one embodiment of the present disclosure. The HMI  500  may be interactive, and may be facilitated for example through the dashboard Head Unit (HU)  580  or through a connected smartphone using an application program interface (API). In the example shown in the figure, the HMI  500  includes a text-based user interface  505  on the display unit  290  of the head unit  580 . Also visible are control knobs  590 . In some embodiments, the HMI  500  is part of, is the same element as, or is in communication with the interface engine  155  or portable device  300 . 
     In the example shown in the figure, the text-based user interface  505  includes a report of completed steps  510  that the trailer lighting diagnostic system has executed, and uncompleted steps  520  that the trailer lighting diagnostic system has not yet executed or is currently executing. In some embodiments, such reports of completed and uncompleted steps enable the trailer lighting diagnostic system to inform the user about the status of the trailer lighting diagnostic system during a fault correction procedure. The text-based interface  505  also includes a user query  530  that poses a question to the user and allows the user to respond. In some embodiments, such user queries enable the trailer lighting diagnostic system to acquire information from the user that may not be available from sensors internal to the vehicle. In some embodiments, such user queries  530  are limited to yes-or-no questions such as “Did the right lamp illuminate?”. In other embodiments, user queries  530  may solicit numerical information from the user such as the flicker rate of a blinker bulb or turn signal indicator bulb  358 . In still other embodiments, user queries may solicit more complex information to be interpreted by a virtual agent. 
     A person of ordinary skill in the art will appreciate that a variety of different user interfaces may be employed to provide information to the user, to request information from the user, and to receive information from the user (e.g., under the control of the interface engine  155  or the portable device  300 ). It is also noted that in many examples no user interaction may be required in order to detect and resolve a problem with a vehicle accessory, component, or subsystem. In some embodiments, the trailer lighting diagnostic system may provide a seamless interaction between the user and the vehicle through the HU  580  or connected device  300  wherein the required user action is conveniently limited to describing the problem and verifying that the problem has been resolved. 
       FIG. 6  is a diagrammatic view of an example augmented reality (AR) display  610  on a portable device  300  such as a smartphone or tablet device. When the vehicle  105  is viewed through the augmented reality display  610 , certain features or subcomponents (e.g., connectors  324  and  334 ) related to a selected diagnostic procedure are highlighted with animated overlays  620  visible only on the display  610 . The animated overlays  620  may show the positions of the subcomponents, in such a way that when the portable device  300  is moved or reoriented, the animated overlays  620  appear to hold a fixed position in real 3D space. The AR display  610  may also include fixed overlays  630  that appear to hold a constant or nearly constant position on the portable device  300 , regardless of the position or orientation of the portable device  300 . 
     Both the animated overlays  620  and fixed overlays  630  may provide graphics, symbols, text, icons, flashing or scrolling indicators, including visual, textual, auditory, or graphical instructions on how to find subcomponents (e.g, a bulb  358 ), or how to interact with subcomponents (e.g.,  324  and  334 ). 
     A number of variations are possible on the examples and embodiments described above. For example, the display  290  could be replaced or supplemented with audible warnings, messages, flashing lights or indicators, data, and recommendations, or with haptic feedback (e.g., vibration of the portable device  300 ). The technology described herein may be implemented on manually controlled vehicles, driver-assist vehicles, or fully autonomous vehicles. The technology described herein may be implemented in diverse combinations of hardware, software, and firmware, depending on the implementation or as necessitated by the structures and modules already present in existing vehicles. 
     Accordingly, the logical operations making up the embodiments of the technology described herein may be referred to variously as operations, steps, objects, elements, components, or modules. Furthermore, it should be understood that these may be arranged in any order, unless explicitly claimed otherwise or a specific order is inherently necessitated by the claim language or by the nature of the component or step. In some instances, the words “light”, “lamp”, and “bulb” may be used interchangeably. 
     All directional references e.g., upper, lower, inner, outer, upward, downward, left, right, lateral, front, back, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, proximal, and distal are only used for identification purposes to aid the reader&#39;s understanding of the claimed subject matter, and do not create limitations, particularly as to the position, orientation, or use of the trailer lighting diagnostic system. Connection references, e.g., attached, coupled, connected, and joined are to be construed broadly and may include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily imply that two elements are directly connected and in fixed relation to each other. The term “or” shall be interpreted to mean “and/or” rather than “exclusive or.” Unless otherwise noted in the claims, stated values shall be interpreted as illustrative only and shall not be taken to be limiting. 
     The above specification, examples and data provide a complete description of the structure and use of exemplary embodiments of the trailer lighting diagnostic system as defined in the claims. Although various embodiments of the claimed subject matter have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of the claimed subject matter. For example, additional sensors such as light sensors, vibration sensors, accelerometers, current sensors, or voltage sensors may be provided to help detect failed components, diagnose failure types, and confirm operational status of vehicle accessories, components, or subsystems. Additionally, sensors external to the vehicle may be employed to provide or supplement any of the sensor or user data described hereinabove, and processors external to the vehicle may be employed to provide or supplement any of the control process steps described hereinabove. Alternatively, machine learning processes or other artificial intelligence (AI) systems may be used to estimate variables from sparse, noisy, or entwined data streams without departing from the spirit of the present disclosure. The principles described above can be equally applied to electric vehicles, internal combustion vehicles, hybrid vehicles, manual vehicles, autonomous and driver-assist vehicles, consumer vehicles, commercial vehicles, and mixed-use vehicles. 
     Still other embodiments are contemplated. It is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative only of particular embodiments and not limiting. Changes in detail or structure may be made without departing from the basic elements of the subject matter as defined in the following claims.