Abstract:
An unattended-vehicle engine-idling system controls a vehicle powertrain in a non-motive mode with the engine running. An ignition switch operables with a removable ignition key. A control circuit has multiple states including a PREARMED state which is entered when the powertrain is in the motive mode and the user generates a manual activation signal. An ARMED state is entered when the transmission is in Park and holds an ignition switch status signal at RUN. An ACTIVE state is entered when the ignition switch is moved to the Accessory or Off positions or the key is removed. The powertrain is switched to non-motive mode and the switch status signal stays at RUN. A DISARMED state is entered in response to a manual deactivation signal generated independently of the ignition switch. In the DISARMED state, the ignition switch status signal corresponds with the ignition switch position, thereby turning off the engine.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not Applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     The present invention relates in general to engine idling of motor vehicles while unattended, and, more specifically, to a control system and method for entering an idling mode in a convenient and efficient fashion while maintaining vehicle security. 
     There are many circumstances in which a user of a vehicle may want to exit their running vehicle and leave it unattended while the engine continues idling. The reasons for doing so may vary depending on the type of user or class of vehicle. Vehicle purchasers typically fall into three categories, namely a retail customer (using the vehicle for typical everyday personal use), a commercial fleet customer (using the vehicle for a business use such as delivery or service), and an emergency/law enforcement customer (for police, ambulance, and fire purposes). 
     A primary reason for continuing to operate the vehicle engine is to maintain operation of other vehicle systems that depend on the engine. For example, a retail customer may want to leave the vehicle running while temporarily stepping away from the vehicle in order to maintain the cabin temperature, which requires continued operation of a heater or air conditioner. A service vehicle in a commercial fleet may be equipped with an elevated lift platform (e.g., cherry picker), and the user may want to leave the vehicle running to maintain power to the elevated lift platform while the platform is elevated. The user of a commercial vehicle being used to deliver merchandise that requires climate control (e.g., food) may need to leave the vehicle running unattended while making deliveries. 
     The emergency fleet customer has countless scenarios where they want to leave their vehicles running while unattended in order to maintain power to their auxiliary emergency equipment (e.g., electronic workstation, lights, video/audio equipment, communication equipment, etc.). For example, the user may leave their vehicle unattended during a traffic stop, crime scene investigation, or a foot pursuit. 
     A remote start function is known wherein a vehicle is started using a wireless remote control without requiring a key in the ignition switch. However, it would be inconvenient and disruptive for the user to obtain unattended idling when exiting the vehicle by a) shutting down the engine, b) removing the key, c) exiting and locking the vehicle, and then d) restarting the engine with a remote control. On the other hand, a vehicle left running unattended with the ignition key in the ignition switch may be at risk of being stolen. 
     One known solution has been utilize a separate key and wireless remote (i.e., FOB) allowing the user to lock/unlock the vehicle doors from outside leaving the key in the ignition with the engine running. However, a perpetrator could break into the vehicle by using a cloned remote device or breaking the window and then driving away. Using a spare mechanical key in a similar fashion is subject to the same problems. 
     Especially with regard to police vehicles, various aftermarket security system add-on devices are known that allow the user to leave the engine running and doors unlocked while preventing unauthorized use of the vehicle. In one type of key-based system, a dedicated button is added to the vehicle for use to activate the system. Once the system is activated and the vehicle is parked, the engine will remain running after the key is removed. The vehicle engine will shut down in response to various conditions, such as the vehicle being shifted out of Park. Otherwise, the vehicle will resume normal operation once the key cylinder is switched to the Run position with the key inserted. Such a system, however, may circumvent existing factory-installed security measures such as a passive anti-theft system (PATS) using a short-range transponder in the key which is electronically read by the vehicle during normal engine starting. Since the engine is already started, the PATS would not prevent theft of the running vehicle by an intruder. 
     Another type of system requires the ignition key to be left in the ignition switch at the Run position but prevents the transmission shifter from being moved out of Park unless the driver to activates a hidden switch to unlock the gearshift locking mechanism. These two events have to happen within a certain window of time, otherwise the locking mechanism will re-activate. The level of protection provided by this system is low because anyone who knows where and how the switch works will have full access to the vehicle, its contents, and operations since the key is present. 
     SUMMARY OF THE INVENTION 
     The present invention provides a system and method to integrate an ignition security system into a vehicle&#39;s electrical and electronic system that will secure an unattended vehicle with its engine idling while providing enhanced security and ease of use. 
     In one aspect of the invention, an unattended-vehicle engine-idling system is provided. A powertrain includes an engine and a transmission having a motive mode and a non-motive mode with the engine running and having an engine off mode. A control circuit is coupled to the engine and the transmission (e.g., the shift lever). An ignition switch is coupled to the control circuit and configured to be operable by a user with a removable ignition key to move to Off, Accessory, Run, and Start positions. The control circuit provides multiple states. A PREARMED state is entered when the powertrain is in the motive mode and the user generates a manual activation signal. An ARMED state is entered from the PREARMED state when the transmission is in a Park position. The ARMED state holds an ignition switch status signal at RUN. An ACTIVE state is entered from the ARMED state when the ignition switch is moved to the Accessory or Off positions or the key is removed from the ignition switch. The ACTIVE state switches the powertrain to the non-motive mode and holds the ignition switch status signal at RUN. A DISARMED state is entered from the ACTIVE state in response to a manual deactivation signal independent of the ignition switch. After entering the DISARMED state in that manner, the ignition switch status signal corresponds with the position of the ignition switch, thereby placing the powertrain in the engine off mode. 
     While in the ACTIVE state, the transmission shift lever is preferably prevented from moving out of the Park position. In addition, the state of the transmission can be monitored so that the engine can be shut down if a position other than Park is detected. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic, block diagram showing vehicle systems and elements involved in various embodiments of the invention. 
         FIG. 2  is a block diagram showing one preferred embodiment for an electronic implementation of the invention. 
         FIG. 3  is a schematic diagram showing parts of a vehicle involved in various embodiments. 
         FIG. 4  is a block diagram showing a preferred embodiment in greater detail. 
         FIGS. 5 and 6  are a flowchart showing one preferred method of the invention. 
         FIG. 7  is a flowchart showing a method for using an ignition switch to generate a manual activation signal for the invention. 
         FIG. 8  is a flowchart showing a method for operating an alarm when an unattended idle is in progress. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The invention is illustrated in connection with an embodiment particularly adapted for use in law enforcement vehicles, referred to herein as Police Idle. This example demonstrates integration with a common vehicle architecture which includes a Body Control Module (BCM) that processes system inputs and outputs, manages system status, and executes various actions. A primary input which activates/deactivates the Police Idle function can be provided by a dedicated momentary push button switch (Police Idle switch) or by using the Start position of the ignition switch as described below. Other standard vehicle components that can be integrated with the Police Idle function include the Brake Transmission Shift Interlock (BTSI) which prevents the gear selector from shifting out of Park, the trunk release switch in the vehicle interior that allows the user to open the trunk without a key or FOB, the power window relay, and the vehicle multiplex network (e.g., CAN) to control various other accessories and for sending and receiving system messages. The invention may further integrate an Instrument Panel Cluster (IPC) that monitors a Park detect switch and displays system status on a message center, a Powertrain Control Module (PCM) which is enabled with a Drive Away Security Enhancement (DASE) feature configured to place the powertrain in a motive (normal) or non-motive (e.g., remote start) mode, and a Smart Data Link Connector (SDLC) that serves as a network gateway between modules, diagnostic tools and equipment. 
     Referring now to  FIG. 1 , a vehicle apparatus  10  includes a powertrain  11  having an internal combustion engine  12  and a transmission  13 . A powertrain control module (PCM)  14  coordinates operation of engine  12  and transmission  13  as known in the art. A body control module (BCM)  15  is connected to an ignition cylinder switch  16  for receiving a signal identifying a physical position of ignition switch  16  including an Off, Accessory, Run, or Start position. BCM  15  provides an ignition status signal to PCM  14  for use in controlling engine  12 . As explained below, BCM  15  can be used to mask an actual position of ignition switch  16  by reporting a different ignition status signal to PCM  14  (e.g., holding the ignition status signal to Run when switch  16  is actually in the Accessory or Off position). 
     An ignition key  17  is configured to mechanically operate ignition switch  16 . For enhanced security, a transponder  18  may be embedded in key  17  for interacting with an engine immobilizer transceiver  19  as known in the art. If an electronic code stored in transponder  18  matches a code stored in module  19 , then an authorization signal may be provided to PCM  14  (which would not otherwise allow the engine to run). 
     For starting engine  12  remotely without inserting a key  17 , a remote start module  20  may be provided as known in the art. When receiving a validated command from a wireless transmitter or FOB (not shown), module  20  sends an activation signal to PCM  14  for starting engine  12 . With the known remote start feature, unattended idling of the engine is achieved while the vehicle remains secure. However, the conventional remote start function cannot be initiated by a driver while in the vehicle or while exiting the vehicle without requiring the engine to first be shut down and the doors to be locked. 
     For some embodiments of the Police Idle function of the present invention, an unattended engine-idle state can be initiated using a dedicated push-button switch  21  which is connected with BCM  15  in order to generate manual activation and/or deactivation signals. In one particularly advantageous embodiment, ignition switch  16  can be used to generate the manual activation signal by moving it into the Start position while the engine is already running. For a law enforcement officer in particular, this can provide a method for setting the Police Idle function that is very fast, intuitive, and done without diverting attention away from the surroundings. 
     As shown in  FIG. 2 , BCM  15  functions as a control circuit including Police Idle system management block  23 . The control circuit may include a microcontroller with appropriate firmware and/or software, for example. An instrument panel cluster (IPC)  24  is comprised of a separate module which is coupled with BCM  15  for monitoring a park position detection switch  25  and for displaying system status messages on a message center forming part of a human machine interface (HMI). 
     A brake transmission shift interlock (BTSI) unit  26  is coupled to BCM  15  and functions in a known manner (i.e., the gear shift selector is locked by a solenoid in the park position unless the ignition switch is in the Run position and the brake pedal is depressed). 
     Police Idle management system  23  includes a switch input management block  30  which is responsive to ignition switch  16  and/or dedicated switch  21  to generate the manual activation and deactivation signals. A hold ignition status block  31  is used to modify the ignition status signal as described below. An inhibit window operation block  32  may prevent the lowering of vehicle windows while the Police Idle function is active, and a hold BTSI block  33  may ensure that the gear shift lock solenoid continuously locks the gear shift lever in the park position while the Police Idle function is active. An inhibit trunk release block  34  is provided for ensuring that a manual trunk release switch contained in the vehicle interior cannot be utilized while the Police Idle function is active. Police Idle management system  23  further includes an immobilizer block  35  that initiates an interrogation of a key transponder during an attempted restoration of the vehicle to normal operation upon return of the user. 
     A diagnostic configuration block  36  is provided for enabling the vehicle manufacturer or a service technician to alter the configuration of BCM  15  by selectably enabling or disabling the Police Idle function. 
       FIG. 3  shows a layout of the various interacting components within vehicle  10  as utilized by the present invention. Thus, vehicle  10  has a driver door  40  having open and closed positions which are sensed by a door position sensor  41 . Power window control buttons  42  may be provided on door  40  for manually controlling the raising or lowering of the vehicle windows. 
     An instrument panel (i.e., dashboard)  43  has various controls accessible to the user including dedicated switch  21 . A gear selector unit  45  includes a shift lever  46  with a lock/unlock button  47  for selecting a transmission setting including a Park position and conventional out-of-park positions. A brake pedal  48  has an associated brake sensor (not shown) which interacts with ignition switch  16  and gear selector  45  to provide the conventional BTSI function. 
     Instrument panel  43  includes a trunk release button  50  for opening a trunk lid  51  via a electronically controlled latch  52 . Instrument panel  43  further provides a cluster area  53  for providing a message center  54 . Other multipurpose switches may be deployed within the vehicle (e.g., on instrument panel  43 ) for interacting with the present invention, including a multipurpose selector switch  56  on steering wheel  55  or various push buttons on a multimedia/climate control panel  57 . User commands entered via these push buttons or via other switches (e.g., a brake pedal switch) can be relayed to the Police Idle system manager to obtain desired functions, such as the shutting down of the engine without using the ignition key as described below. 
     The Police Idle system manager can be implemented in any one or more of the various electronic modules that may be present in any particular vehicle model, which may or may not include a body control module. Such modules and various sensors and actuators may typically communicate over a multiplex bus  60 , thereby allowing the Police Idle system manager to interact with a wide range of vehicle systems. For example, the Police Idle control circuit may interact over bus  60  with a vehicle security system including an alarm generator  61  (e.g., a vehicle horn and/or exterior lights that can be triggered for generating an audible and visible alarm). Other auxiliary accessories that should be locked or inhibited during Police Idle activation may be connected either directly or via multiplex bus  60  such as a remotely-controlled gun rack  62 . During Police Idle activation with the vehicle unattended, a status message sent to gun rack  62  would cause automatic locking so that a stored gun could not be accessed while a police officer was away from the vehicle, for example. 
       FIG. 4  shows various signals that may be communicated during operation of the invention. An Ignition_Status signal provided from BCM  15  to PCM  14  normally identifies the physical position of ignition switch  16  (together with an identification whether the ignition key is present, obtained from an in-key detector (IKD) sensor  65 ). In addition, a control signal is provided to PCM  14  to indicate whether the Police Idle function is active so that a drive-away security enhancement (DASE)  64  feature of PCM  14  may be appropriately activated to ensure that the vehicle cannot be driven as long as Police Idle remains active (e.g., by cutting the engine if the transmission leaves the Park position). PCM  14  provides an engine status signal to BCM  15  indicative of whether the engine is running or has stalled. 
     BCEM  15  includes a configurable memory location  66  which is set by the manufacturer or a service technician in order to either enable or disable the police idle function depending on whether the vehicle is actually used by a law enforcement organization, for example. For the purpose of setting the contents of memory  66 , a diagnostic tool may be connected via smart data link connector (SDLC)  73  to perform a programming sequence including the writing of police secure idle configuration data (PoliceIdle_Enable_Cfg). A diagnostic response signal may be provided to the diagnostic tool via SDLC  73  to confirm a programming action. 
     As shown in  FIG. 4 , BCM  15  may communicate with IPC  54  via SDLC  73 . Data/text to be displayed on a message center  72  is sent or identified by a police idle mode status signal (PoliceIdleMode_D_Stat) from BCM  15  to IPC  54 . As shown in  FIG. 4 , a message may be displayed on message center  72  explaining what action is necessary during a Police Idle activation in order to cancel the Police Idle function (i.e., shut down the engine idle). A Delay_Acc signal is controlled by BCM  15  in order to inhibit power window operation when Police Idle is Active. 
     As also shown in  FIG. 4 , a custom accessory  62  (such as a gun rack) can be directly connected to an auxiliary control output  67  instead of by a multiplex message. 
       FIG. 4  also shows a conventional delay accessory relay  70  for powering a plurality of window switches and motors  71 . A global close/open power window command block  68  in BCM  15  is configured to inhibit any opening commands while the Police Idle function is active in order to enhance the security of any vehicle contents while the vehicle is unattended. 
     A preferred method of the invention will be described in connection with the flowchart of  FIGS. 5 and 6 . The method begins when the vehicle is started in step  75 . In step  76 , a configuration bit in the BCM is checked. This configuration bit may be enabled at the factory per a customer order code, for example. A service tool can be used to disable the configuration if desired (e.g., decommissing a police vehicle for re-sale). If not configured for Police Idle operation, the method does not progress beyond step  76 . If the configuration is enabled, a check is performed to determine whether the vehicle operator put the ignition switch in RUN in step  77  and whether the engine is running in motive mode in step  79  (wherein motive mode means that torque is available to operate the vehicle, whereas non-motive mode means that the engine is running but torque is not available to operate the vehicle). If either of these conditions is not satisfied, then the Police Idle function remains in a DISARMED state  78 . 
     Once it is confirmed that the vehicle is running in motive mode, a check is performed in step  80  to determine whether a manual Police Idle activation signal is generated. Thus, the Police Idle control circuit will wait in DISARMED state  78  until the vehicle operator initiates a “button press” which puts the control circuit into a PREARMED state  81 . As previously mentioned, the invention may use two alternative methods for the user to initiate a “button press.” The first method uses a dedicated momentary push button, and the second method uses the ignition switch (i.e., key cylinder). The ignition switch has four unique positions (Off, Accessory (ACC), Run, or Start). To start the vehicle, the user inserts the key into the ignition switch and rotates it from Off to Start to Run. After the vehicle is running, the Start position of the ignition switch is used to activate the Police Idle system. Thus, the vehicle operator can PREARM the Police Idle function by rotating the key from Run to Start. The integrated ignition switch is a simple solution that avoids the cost and space required to package a dedicated switch. It also allows a police officer to quickly activate the Police Idle function and remove the key with a one-handed operation, which can be important during an emergency situation. 
     While in PREARMED state  81 , the IPC is preferably illuminated with a telltale (e.g., a yellow indicator lamp) on the message center to alert the vehicle operator that the system is PREARMED. The Police Idle control circuit will transition to an ARMED state  86  once a gear shift position of Park is detected in a step  85 , unless any of the conditions monitored in steps  82 - 84  are detected first. Thus, a check is performed in step  82  to determine whether the user disables the engine by moving the ignition key out of Run position before placing the gear selector in Park position. In addition, a check is performed in step  83  to determined whether the engine has not stalled. If the engine is not running in either instance, then the control circuit transitions back to DISARMED state  78 . Furthermore, a check is performed in step  84  to determine whether the user has performed another manual trigger of the Police Idle button which is interpreted as a deactivation signal (i.e., by returning to DISARMED state  78 ). 
     When the Park position is detected in step  85 , then the method proceeds via point A to ARMED state  86  in  FIG. 6 . In ARMED state  86 , the telltale on the IPC will continue to illuminate (e.g., a yellow indicator lamp) and the BCM control circuit will hold the Ignition_Status signal at a value indicating the Run position. As already mentioned, the Ignition_Status signal is comprised of a message sent via the CAN bus that normally represents the physical position of the ignition switch. By altering the message to have a value of “Run” in order to mask the signal, the engine remains running and other vehicle subsystems will remain operational when the user switches the ignition switch to Off (so that the climate control and electrical accessories other than those associated with the motive mode of the vehicle can continue to function normally). 
     Once the BCM control circuit is in ARMED state  86 , it will either transition to an ACTIVE state  90  or back to DISARMED state  78  via point B. Transitioning back to DISARMED state  78  occurs if the user initiates another “button press” (i.e., cancels the system) in step  87  or if a vehicle stall is detected in step  88 . Otherwise, the system will activate (i.e., go to ACTIVE state  90 ) when the user switches the ignition switch to Off or Accessory in step  89 . As a result of entering ACTIVE state  90 , the telltale on the IPC will change colors (e.g., green) to indicate that the system is active and the system will activate security measures to allow the vehicle operator to leave the vehicle unattended yet secure. Such actions preferably include:
         Holding the BTSI in the locked position to prevent the vehicle gear selector from shifting out of PARK.   Inhibiting the power windows from operating.   Placing the PCM in non-motive (DASE) mode. This is an added layer of security in the event that the BTSI lock is defeated. When in the non-motive mode, the PCM will shut down the engine if the gear selector is shifted out of PARK or if vehicle speed is detected.   Disabling the trunk release button in the cabin of the vehicle to prevent unauthorized access to any contents stowed away in the trunk (e.g., weapons, evidence, uniforms, etc. . . . ). The key cylinder and remote FOB would still have access to the trunk.   Transmitting a CAN message for use by customized auxiliary security equipment (e.g., lock for a gun rack).   If enabled by the user, sounding an alarm if someone enters the vehicle without the key (described in more detail below in connection with  FIG. 8 ).       

     Upon returning to the vehicle with the Police Idle control circuit in ACTIVE state  90 , the user will need the key to resume normal vehicle operation. If either the key or user is not available (for example, a lost key or an injured officer), an alternative method may be needed to shut down the vehicle. Specific shutdown actions can be detected in step  91 . For example, if the vehicle is equipped with a dedicated Police Idle switch, then a button press generates a manual deactivation signal which is detected in step  91  and causes the control circuit to return to DISARMED state  78  via point B so that the engine shuts down. Alternatively, the message center can display instructions for shutting down the vehicle using other means such as multifunction switches on the steering wheel or instrument panel or a brake pedal switch. Example instructions include:
         “PRESS &amp; HOLD BRAKE PEDAL TO SHUT DOWN VEHICLE”   “DOUBLE TAP THE BRAKE PEDAL TO SHUT DOWN VEHICLE”   “PULL &amp; HOLD GEAR SHIFT LEVER TO SHUT DOWN VEHICLE”   “PRESS &amp; HOLD OK TO SHUT DOWN VEHICLE”
 
Note that sequences such as the “press &amp; hold” and the “double tap” steps alleviate inadvertent shut down during ingress or egress by a user. In addition to the alternate shutdown options, the method continues to check for an engine stall in step  92  and returns to DISARMED state  78  in the event of a stall.
       

     Assuming the key is available, then the user can resume normal vehicle operation by using the key to switch the ignition back into the Run or Start position in step  93 . The BCM control circuit then transitions to a POST-ARMED state  94 . The purpose of POST-ARMED state  94  that if the vehicle is equipped with an engine immobilizer system (i.e., passive anti-theft system), then the immobilizer authentication process will initiate and validate the key before disarming the Police Idle function. Thus, a check is performed in step  96  to determine whether the vehicle has an enabled immobilizer system. If not, then a transition is made to DISARMED state  78  via point B and the vehicle operates normally in response to the key operating the ignition switch. If the immobilizer is enabled, then a key read is initiated in step  97  and authentication of the key is checked in step  98 . If valid, then a transition is made to DISARMED state  78  via point B and the vehicle operates normally. If not valid, then a check is performed in step  95  to determine if the ignition returns to Off or Acc positions. If so, then a return is made to the main loop for ACTIVE state  90 . Otherwise, the immobilizer continues to check for a valid key. 
       FIG. 7  discloses a method for filtering a signal generated by the ignition switch in response to the Start position of the ignition switch so that a manual activation of the Police Idle function can be reliably detected. A check is performed in step  100  to determine whether the factory configuration has been enabled for performing the Police Idle function. If so, then an engine status is checked in step  101  to determine whether the powertrain is in the motive mode. If not, then a return is made to step  100 . Otherwise, a check is performed in step  102  to determine whether a transition has been made in the ignition switch position from the Run to the Start position. If not, then a value for a Button signal maintained by the control circuit is set to “NOT_PRESSED” in step  103 . When ignition switch movement from Run to Start is detected in step  102 , then a PRESSED_Timer is started in step  104 . 
     Next, a check is performed in step  105  to determine whether a continuously incrementing value of PRESSED_Timer reaches a predetermined time of x milliseconds (e.g., about 500 mS). If not, then a check is performed in step  106  to determine whether the ignition switch position has stayed at the Start position. Thus, steps  105  and  106  work together to ensure that the ignition switch position is continuously detected at Start for the predetermined time, so that any shorter, inadvertent movement is ignored. Thus, if the Start position is not detected in step  106 , then the PRESSED_Timer is reset in step  107 . 
     When step  105  detects that the key position has remained at the Start position for the predetermined amount of time, then the PRESSED_Timer is reset in step  108  and the value of the Button signal is set to “PRESSED” in step  109 . Next, a predetermined duration for maintaining the “PRESSED” value for the Button signal is synthesized by starting a NOT_PRESSED_Timer in step  110 , and waiting until the NOT_PRESSED_Timer reaches a predetermined time (e.g., x milliseconds) in step  111  before resetting the NOT_PRESSED_Timer in step  112  and updating the value of the Button signal to NOT_PRESSED in step  103 . Preferably, a check may also be performed to confirm that the ignition switch is not still in the Start position before moving to step  103 . 
       FIG. 8  illustrates one preferred method for generating an alarm signal in the event that an intruder enters the vehicle during the Police Idle function without using the ignition key to cancel the Police Idle function. Thus, a check is performed in step  120  to determine whether the user has enabled the alarm function. If not, then the method ends at step  132 . If enabled, then a check is performed in step  121  to determine whether the ACTIVE state of Police Idle has been entered. Once in the ACTIVE state, a courtesy timer is reset in step  122  to allow the user a predetermined time to re-enter the vehicle after closing the door in case the situation changes and they do not want to perform the Alarm function. Thus, a check is performed in step  123  to detect closing of the door, and in response to closing of the door the courtesy timer is started in step  124 . A check is performed in step  125  to determine whether the courtesy timer has expired. If not, then a check is performed in step  126  to determine whether the driver door has been reopened. If not, then another check is made for expiration of the timer in step  125 . If the door is detected as open in step  126 , then a return is made to step  121  since it will be assumed that the user changed their mind about leaving the vehicle unattended just yet. 
     Upon expiration of the courtesy timer in step  125 , it is assumed that the driver did leave the area. Thus, the method waits until a opening of the driver door is detected in step  127 . Once the driver door opens, an alarm timer is started and the message center displays a warning message directing the user to reinsert the ignition key to cancel the alarm within a predetermined number of seconds. A check is performed in step  129  to determine whether the alarm timer has expired. If it has, then the alarm is sounded in step  130 . If it has not yet expired, then a check is performed in step  131  to determine whether the user has reinserted the key and canceled the alarm. If so, then the procedure ends at step  132 . Otherwise, it returns made to step  129  to re-check for expiration of the alarm timer. Once the alarm is sounded in step  130 , the controller continues to check for reinsertion of the key so that the alarm can be terminated.