Abstract:
A vehicle ready light control method includes providing a vehicle having a vehicle ready light and illuminating the vehicle ready light when a powertrain of the vehicle is enabled and at least one of the following conditions exists: the vehicle is in park mode or neutral mode; an engine RPM speed of the vehicle is below a predetermined RPM value and a wheel speed of the vehicle is below a predetermined wheel speed. A vehicle ready light control system is also disclosed.

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present disclosure relates to a vehicle ready light which indicates whether a hybrid electric vehicle is ready for operation. More particularly, the present disclosure relates to a vehicle ready light control method and system which determines whether a vehicle ready light is illuminated. 
     BACKGROUND OF THE INVENTION 
     Hybrid electric vehicles (HEVs) may include a vehicle ready light which is illuminated to indicate to a driver of the vehicle that the vehicle is ready to be operated. The light may be illuminated whenever the hybrid powertrain (either the engine or the electric traction drive) is enabled. A signal from the Powertrain Control Module indicates that the vehicle has been started by the driver and initiates and sustains illumination of the vehicle ready light, which remains illuminated until the vehicle ignition key is turned off. The purpose of the light is to warn the driver that, absent the noise and vibration of the engine, the vehicle is still operational and therefore, when the vehicle is placed into drive and the brake is released, the vehicle will move forward. However, the vehicle ready light may remain illuminated continually and annoy the driver, particularly at night. Moreover, because the vehicle ready light is on continually, the safety function of the light may be ignored as the light fades into the driver&#39;s background consciousness. 
     Therefore, a vehicle ready light control method and system which determines whether a vehicle ready light is illuminated is needed. 
     SUMMARY OF THE INVENTION 
     The present disclosure is generally directed to a control method for a vehicle ready light of a vehicle. An illustrative embodiment of the control method includes providing a vehicle having a vehicle ready light and illuminating the vehicle ready light when a powertrain of the vehicle is enabled and at least one of the following conditions exists: the vehicle is in park mode or neutral mode; an engine RPM speed of the vehicle is below a predetermined RPM value and a wheel speed of the vehicle is below a predetermined wheel speed. 
     The present disclosure is further generally directed to a vehicle ready light control system. An illustrative embodiment of the system includes a powertrain control module; at least one of an engine sensor, wheel speed sensors and a gear selector; an instrument cluster controller interfacing with the powertrain control module and the engine sensor, wheel speed sensors and/or gear selector; and a vehicle ready light interfacing with the instrument cluster controller. The instrument cluster controller is adapted to receive a powertrain enablement signal from the powertrain control module and at least one of an engine RPM signal from the engine sensor, a wheel speed indication signal from the wheel speed sensors and a gear selector signal from the gear selector. The instrument cluster controller is adapted to illuminate the vehicle ready light when the powertrain enablement signal is received from the powertrain control module and at least one of the following conditions exists: The engine RPM signal indicates an engine RPM below a predetermined RPM value, the wheel speed indication signal indicates a wheel speed below a predetermined wheel speed value and the gear selector signal indicates a vehicle park mode or a vehicle neutral mode. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will now be made, by way of example, with reference to the accompanying drawings, in which: 
         FIG. 1  is a flow diagram which illustrates an illustrative embodiment of a vehicle ready light control method; 
         FIG. 2  is a flow diagram which illustrates an illustrative control algorithm suitable for implementation of an illustrative embodiment of the vehicle ready light control method; and 
         FIG. 3  is a block diagram of an illustrative embodiment of a vehicle ready light control system. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following detailed description is merely exemplary in nature and is not intended to limit the described embodiments or the application and uses of the described embodiments. As used herein, the word “exemplary” or “illustrative” means “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” or “illustrative” is not necessarily to be construed as preferred or advantageous over other implementations. All of the implementations described below are exemplary implementations provided to enable persons skilled in the art to make or use the disclosure and are not intended to limit the scope of the disclosure, which is defined by the claims. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description. 
     Referring initially to  FIGS. 1 and 2 , a flow diagram  100  which illustrates an illustrative embodiment of a vehicle ready light control method is shown in  FIG. 1 . An illustrative control algorithm  200  which is suitable for implementation of an illustrative embodiment of the vehicle ready light control method  100  is shown in  FIG. 2 . In block  102  of the flow diagram  100  in  FIG. 1 , a vehicle such as a hybrid electric vehicle (HEV) may be turned on such as by turning of an ignition key, for example and without limitation. In block  104 , a vehicle ready light is illuminated. In block  106 , a three-second or other time interval may elapse. 
     In block  108 , input from multiple sources may be provided. The input may include a powertrain enablement signal which is provided by a Powertrain Control Module (PCM) of the vehicle and indicates enablement of the powertrain of the vehicle. The input may additionally include any combination of the following: an engine RPM signal which is provided by an engine sensor of an engine (which may be powered by gasoline, diesel, liquid natural gas or other fuel) of the vehicle and indicates the engine RPM of the engine; a wheel speed indication signal which is provided by wheel speed sensors of the vehicle and indicates the forward speed of the vehicle; and a gear selector signal which is provided by a gear selector of the vehicle and indicates whether the vehicle is in park, neutral, drive or reverse mode. 
     In block  110 , the input from the multiple sources may be analyzed in a manner which will be hereinafter described. In block  112 , based on analysis of the input which was made in block  110 , a determination may be made as to whether illumination of the vehicle ready illumination light is to be continued. In block  114 , illumination of the vehicle ready light may be continued or discontinued based on the determination which was made in block  112 . In block  116 , the vehicle may ultimately be turned off such as by turning of the ignition key, for example and without limitation. In block  118 , the vehicle ready light is turned off if the vehicle ready light was illuminated upon turning of the vehicle off in block  116 . 
     Analysis of the input from the various sources in block  110  of the flow diagram  100  in  FIG. 1  may be implemented according to the algorithm  200  which is shown in  FIG. 2 . In block  202 , a determination is made as to whether the powertrain of the vehicle is enabled. The powertrain is typically enabled upon turning of the vehicle on in block  102  of  FIG. 1 . If the powertrain of the vehicle is not enabled, the vehicle ready light is turned off in block  204 . If the powertrain of the vehicle is enabled, one or more additional determinations may be made to determine whether the vehicle ready light is illuminated. 
     In block  206 , a determination may be made as to whether the vehicle is in either park or neutral mode. If the vehicle is in either park or neutral, the vehicle ready light may be illuminated in block  208 . If the vehicle is not in either park or neutral, a determination may be made as to whether the engine speed RPM of the engine of the vehicle is less than a predetermined rpm value (such as 500 rpm, for example and without limitation), in block  210 . If the engine speed RPM is not less than the predetermined RPM value, the vehicle ready light may be turned off in block  212 . If the engine speed RPM is less than the predetermined RPM value, a determination may be made as to whether the wheel speed of the vehicle is less than a predetermined wheel speed value (such as 3 mph, for example and without limitation) in block  214 . If the wheel speed is not less than the predetermined wheel speed value, the vehicle ready light may be turned off in block  216 . If the wheel speed is less than the predetermined wheel speed value, the vehicle ready light may be turned on in block  218 . 
     Referring next to  FIG. 3 , a block diagram  300  which illustrates an illustrative embodiment of a vehicle ready light control system, hereinafter system, is shown. The system  300  includes a powertrain control module  302  of a hybrid electric vehicle (HEV), for example and without limitation. The system  300  may further include at least one of an engine sensor  304 , wheel speed sensors  306  and a gear selector  308 . An instrument cluster controller  310  may interface with the powertrain control module  302 , the engine sensor  304 , the wheel speed sensors  306  and the gear selector  308 . A vehicle ready light  312  may interface with the instrument cluster controller  310 . 
     In the system  300 , the powertrain control module  302  is adapted to transmit a powertrain enablement signal  302   a  to the instrument cluster controller  310  in the event that the powertrain (not shown) of the vehicle is enabled. The engine sensor  304  may be adapted to transmit an engine RPM signal  304   a , which indicates the RPM of an engine (not shown) of the vehicle, to the instrument cluster controller  310 . The wheel speed sensors  306  may be adapted to transmit a wheel speed indication signal  306   a  which indicates the wheel speed of the vehicle (not shown) to the instrument cluster controller  310 . The gear selector  308  may be adapted to transmit a gear selector signal  308   a  which indicates whether the vehicle is in a park mode, a neutral mode, a forward drive mode or a reverse mode to the instrument cluster controller  310 . Responsive to receiving the powertrain enablement signal  302   a  and at least one of the engine RPM signal  304   a , the wheel speed indication signal  306   a  and the gear selector signal  308   a , the instrument cluster controller  310  may be adapted to analyze the signals and determine whether or not to illuminate the vehicle ready light  312  via a vehicle light activation signal  314  as will be hereinafter described. 
     In an exemplary implementation of the system  300 , if the powertrain (not shown) of the vehicle is not enabled, the powertrain control module  302  may not transmit a powertrain enablement signal  302   a  to the instrument cluster controller  310 . In that case, the instrument cluster controller  310  may maintain the vehicle ready light  312  in an “off” state. If, on the other hand, the powertrain of the vehicle is enabled, the powertrain control module  302  may transmit a powertrain enablement signal  302   a  to the instrument cluster controller  310 . 
     The instrument cluster controller  310  may next determine whether the vehicle is in park, neutral, forward or reverse mode. If the gear selector signal  308   a  which is received from the gear selector  308  indicates that the vehicle is in either park mode or neutral mode, the instrument cluster controller  310  may illuminate the vehicle ready light  312  via the vehicle light activation signal  314 . If on the other hand the gear selector signal  308   a  indicates that the vehicle is not in either park mode or neutral mode, the instrument cluster controller  310  may determine whether the RPM of the engine (not shown) of the vehicle is below a predetermined RPM value. If the engine RPM signal  304   a  which is received from the engine sensor  304  indicates that the RPM of the engine does not fall below a predetermined RPM value (such as 500 rpm, for example and without limitation), the instrument cluster controller  310  may maintain the vehicle ready light  312  in the “off” state. 
     On the other hand, if the RPM of the engine does fall below the predetermined RPM value, the instrument cluster controller  310  may next determine whether the wheel speed of the vehicle is below a predetermined wheel speed. If the wheel speed indication signal  306   a  indicates that the wheel speed of the vehicle does not fall below the predetermined wheel speed, the instrument cluster controller  310  may maintain the vehicle ready light  312  in the “off” state. On the other hand, if the wheel speed indication signal  306   a  indicates that the wheel speed of the vehicle does fall below the predetermined wheel speed, the instrument cluster controller  310  may illuminate the vehicle ready light  312  via the vehicle ready light activation signal  314 . 
     While the preferred embodiments of the disclosure have been described above, it will be recognized and understood that various modifications can be made in the disclosure and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the disclosure.