Part 2

OPERATION

FOG LAMP INDICATOR

The fog lamp indicator gives an indication to the vehicle operator whenever the optional fog lamps are illuminated. This indicator is controlled by the Instrument Panel Cluster (IPC) circuit board based upon IPC programming and electronic messages received by the IPC from the Body Control Module (BCM) over the Controller Area Network (CAN) data bus.

The fog lamp indicator is completely controlled by the IPC logic circuit, and that logic will only allow this indicator to operate when the IPC receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the indicator will always be OFF when the ignition switch is in any position except ON or START. The indicator only illuminates when it is energized by the IPC logic circuit. The IPC will turn ON the fog lamp indicator for the following reasons:

- Fog Indicator Lamp-On Message - Each time the cluster receives an electronic fog indicator lamp-ON message from the BCM indicating the fog lamp circuit is energized, the fog lamp indicator will be illuminated. The indicator remains illuminated until the cluster receives a lamp-OFF message from the BCM, until the ignition switch is turned to the OFF position or until the exterior lamp load shedding (battery saver) timed interval expires, whichever occurs first.

The BCM continually monitors electronic exterior lighting switch status messages from the IPC to determine the appropriate outputs to the fog lamps. The BCM activates or deactivates the fog lamp circuit then sends the proper lamp-ON or lamp-OFF message back to the IPC. For further diagnosis of the fog lamp indicator or the IPC circuitry that controls the indicator Testing and Inspection.

HIGH BEAM INDICATOR

The high beam indicator gives an indication to the vehicle operator whenever the headlamp high beams are illuminated. This indicator is controlled by a transistor on the Instrument Panel Cluster (IPC) board based upon cluster programming and a hard wired multiplex input received by the cluster from the headlamp beam select switch circuitry of the multi-function switch on the washer/beam select switch mux circuit.

The high beam indicator Light Emitting Diode (LED) is completely controlled by the IPC logic circuit, and that logic will allow this indicator to operate whenever the IPC receives a battery current input on the fused B(+) circuit. Therefore, the LED can be illuminated regardless of the ignition switch position. The LED only illuminates when it is provided a path to ground by the IPC transistor. The IPC will turn ON the high beam indicator for the following reasons:

- High Beam Headlamps-On Input - Each time the IPC detects a high beam headlamps-ON input from the headlamp beam select switch circuitry of the multi-function switch on the washer/beam select switch mux circuit, the headlamp high beams and the high beam indicator will be illuminated. The indicator remains illuminated until the cluster receives a high beam headlamps-OFF input from the multi-function switch, or until the exterior lamp load shedding (battery saver) timed interval expires, whichever occurs first.

The IPC continually monitors the headlamp switch and the multi-function switch to determine the proper headlamp low beam and high beam control. The IPC then sends the proper electronic low beam and high beam lamp-ON and lamp-OFF messages to the Body Control Module (BCM) over the Controller Area Network (CAN) data bus and controls the high beam indicator operation accordingly. For further diagnosis of the high beam indicator or the instrument cluster circuitry that controls the indicator Testing and Inspection.

LOW OIL PRESSURE INDICATOR

The low oil pressure indicator gives an indication to the vehicle operator when the engine oil pressure reading reflects a condition requiring immediate attention. This indicator is controlled by a transistor on the Instrument Panel Cluster (IPC) circuit board based upon IPC programming and electronic messages received by the cluster from the PCM over the Controller Area Network (CAN) data bus.

The low oil pressure indicator Light Emitting Diode (LED) is completely controlled by the IPC logic circuit, and that logic will only allow this indicator to operate when the IPC receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the LED will always be OFF when the ignition switch is in any position except ON or START. The LED only illuminates when it is provided a path to ground by the instrument cluster transistor. The IPC will turn ON the low oil pressure indicator for the following reasons:

- Engine Oil Pressure Low Message - Each time the cluster receives an electronic engine oil pressure message from the PCM indicating the pressure is about 6.9 kPa (1 psi) or lower, the low oil pressure indicator will be illuminated. The indicator remains illuminated until the cluster receives a message from the PCM indicating that the pressure is above about 6.9 kPa (1 psi), or until the ignition switch is turned to the OFF position, whichever occurs first. The IPC will only turn the indicator ON in response to low engine oil pressure if the engine speed is greater than zero.

The PCM continually monitors the engine oil pressure sensor to determine the engine oil pressure. The PCM then sends the proper messages to the IPC. For further diagnosis of the low oil pressure indicator or the IPC circuitry that controls the LED Testing and Inspection.

LOW TIRE PRESSURE

The Tire Pressure Monitor System (TPMS) indicator gives an indication to the vehicle operator of the status of the TPMS system. This indicator is controlled by a transistor on the Instrument Panel Cluster (IPC) circuit board based upon cluster programming and electronic messages received by the IPC from the Wireless Ignition Node over the Controller Area Network (CAN) data bus.

The TPMS indicator Light Emitting Diode (LED) is completely controlled by the IPC logic circuit, and that logic will only allow this indicator to operate when the IPC receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the LED will always be OFF when the ignition switch is in any position except ON or START. The LED only illuminates when it is provide a path to ground by the IPC transistor. Each time the ignition switch is turned to the ON position, the WIN sends an electronic TPMS indicator lamp-ON message to the cluster to illuminate the TPMS indicator for about three seconds as a bulb test. The instrument cluster will turn ON the TPMS indicator for the following reasons:

- TPMS Indicator Lamp-On Message - Each time the IPC receives an electronic TPMS indicator lamp-ON message from the WIN, the TPMS indicator will be illuminated. The indicator can be flashed ON and OFF, or illuminated solid, as dictated by the WIN message. The indicator remains illuminated until the IPC receives a lamp-OFF message from the WIN or until the ignition switch is turned to the OFF position, whichever occurs first.

- Communication Error - If the cluster receives no TPMS lamp-ON or lamp-OFF messages from the WIN for six consecutive seconds, the TPM indicator is illuminated by the IPC. The indicator remains controlled and illuminated by the IPC until a valid lamp-ON or lamp-OFF message is received from the WIN.

The WIN performs a self-test each time the ignition switch is turned to the ON position to decide whether the TPMS is in good operating condition and whether the tire inflation pressures are too high or too low. The WIN then sends the proper lamp-ON or lamp-OFF message to the IPC. If the IPC turns ON the TPMS indicator after the bulb test, it indicates that the inflation pressure of a tire is too low or that a malfunction has occurred and the TPMS is ineffective.

MALFUNCTION INDICATOR

The MIL gives an indication to the vehicle operator when the PCM or the PCM has recorded a Diagnostic Trouble Code (DTC) for an On-Board Diagnostics II (OBDII) emissions-related circuit or component malfunction. The MIL is controlled by a transistor on the Instrument Panel Cluster (IPC) circuit board based upon IPC programming and electronic messages received over the Controller Area Network (CAN) data bus. These electronic messages are received from the PCM or PCM, depending on engine application.

The MIL Light Emitting Diode (LED) is completely controlled by the IPC logic circuit, and that logic will only allow this indicator to operate when the IPC receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the LED will always be OFF when the ignition switch is in any position except ON or START. The LED only illuminates when it is provided a path to ground by a transistor on the IPC circuit board. Each time the ignition switch is turned to the ON position the indicator is illuminated for about two seconds as a bulb test. The entire bulb test is a function of the PCM. The MIL will be turned ON for the following reasons:

- MIL Lamp-On Message - Each time the IPC receives an electronic MIL lamp-ON message from the PCM or ECM, the indicator will be illuminated. The indicator can be flashed ON and OFF, or illuminated solid, as dictated by the PCM. For some DTCs, if a problem does not recur, the PCM or ECM will send a lamp-OFF message automatically. Other DTCs may require that a fault be repaired and the PCM or ECM be reset before a lamp-OFF message will be sent.

- Communication Error - If the IPC receives no lamp-ON or lamp-OFF messages from the PCM or ECM for about 10 seconds, the MIL is illuminated by the IPC to indicate a loss of bus communication. The indicator remains controlled and illuminated by the cluster until a valid message is received from the PCM.

The PCM or ECM continually monitors the fuel and emissions system circuits and sensors to decide whether the system is in good operating condition. The PCM or ECM then sends the proper lamp-ON or lamp-OFF message to the IPC. For further diagnosis of the MIL or the IPC circuitry that controls the LED Testing and Inspection. If the IPC turns ON the MIL after the bulb test, it may indicate that a malfunction has occurred and that the fuel and emissions systems may require service.

SEATBELT INDICATOR

The seatbelt indicator gives an indication to the vehicle operator of the status of the driver side front seatbelt. This indicator is controlled by a transistor on the Instrument Panel Cluster (IPC) circuit board based upon IPC programming and a hard wired input from the seatbelt switch in the driver side front seatbelt buckle through the seat belt indicator driver circuit.

The seatbelt indicator also includes a programmable enhanced seatbelt reminder or BELTMINDER feature that is enabled when the vehicle is shipped from the factory. This BELTMINDER feature can be disabled and enabled by the customer using a specific programming event sequence, or by the dealer using a diagnostic scan tool.

The seatbelt indicator Light Emitting Diode (LED) is completely controlled by the IPC logic circuit, and that logic will only allow this indicator to operate when the IPC receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the LED will always be OFF when the ignition switch is in any position except ON or START. The LED only illuminates when it is provided a path to ground by the IPC transistor. The IPC will turn ON the seatbelt indicator for the following reasons:

- Seatbelt Reminder Function - Each time the IPC receives a battery current input on the fused ignition switch output (run-start) circuit, the indicator will be illuminated as a seatbelt reminder for about six seconds, or until the ignition switch is turned to the OFF position, whichever occurs first. This reminder function will occur regardless of the status of the seatbelt switch input to the IPC.

- Driver Side Front Seatbelt Not Buckled - Beltminder Active - Following the seatbelt reminder function, each time the cluster detects an open circuit on the seat belt indicator driver circuit (seatbelt switch open = seatbelt unbuckled) with the ignition switch in the START or ON positions, the indicator will be illuminated. In addition, if the driver side front seat belt remains unbuckled about 60 seconds after the conclusion of the seatbelt reminder function with the vehicle speed greater than about 8 kilometers-per-hour (5 miles-per-hour), the seatbelt indicator will begin to cycle between flashing ON and OFF for 3 seconds, then lighting solid for 2 seconds. The seatbelt indicator will continue to cycle between flashing and solid illumination for 13 complete cycles, until the seat belt indicator driver input to the cluster is closed to ground (seatbelt switch closed = seatbelt buckled), or until the ignition switch is turned to the OFF position, whichever occurs first.

- Driver Side Front Seatbelt Not Buckled - Beltminder Inactive - Following the seatbelt reminder function, each time the IPC detects an open circuit on the seat belt indicator driver circuit (seatbelt switch open = seatbelt unbuckled) with the ignition switch in the START or ON positions, the indicator will be illuminated. The seatbelt indicator remains illuminated until the seat belt indicator driver input to the cluster is closed to ground (seatbelt switch closed = seatbelt buckled), or until the ignition switch is turned to the OFF position, whichever occurs first.

- Airbag Indicator Backup - If the IPC detects a fault in the airbag indicator circuit it will send an electronic message indicating the fault to the Occupant Restraint Controller (ORC), then flash the seatbelt indicator ON and OFF. The IPC will continue to flash the indicator until the airbag indicator circuit fault is resolved, or until the ignition switch is turned to the OFF position, whichever occurs first.

SECURITY SYSTEM INDICATOR

The security indicator gives an indication to the vehicle operator when the Vehicle Theft Security System (VTSS) is arming or is armed. On vehicles equipped with the Sentry Key Immobilizer System (SKIS), the security indicator also gives an indication to the vehicle operator of the status of the SKIS. This indicator is controlled by a transistor on the Instrument Panel Cluster (IPC) circuit board based upon IPC programming, hard wired inputs to the IPC from the various security system components, and electronic messages received by the cluster from the Wireless Ignition Node (WIN) via the Body Control Module (BCM) over the Controller Area Network (CAN) data bus.

The security indicator Light Emitting Diode (LED) is completely controlled by the instrument cluster logic circuit, and that logic will allow this indicator to operate whenever the IPC receives a battery current input on the fused B(+) circuit. Therefore, the LED can be illuminated regardless of the ignition switch position. The LED only illuminates when it is provided a path to ground by the IPC transistor. Depending upon the programmed condition the indicator can be illuminated solid, flashed at a slow rate (0.5 Hertz, 12.5 percent duty cycle), or flashed at a fast rate (1 Hertz, 50 percent duty cycle). Each time the ignition switch is turned to the ON position the security indicator illuminates for about two seconds as a bulb test. The entire bulb test is a function of the WIN. The IPC will turn ON the security indicator for the following reasons:

- VTSS Indication - During the 16 second VTSS arming function, the cluster will flash the security indicator ON and OFF repeatedly at a steady, fast rate to indicate that the VTSS is in the process of arming. Following successful VTSS arming, the cluster flashes the security indicator ON and OFF continuously at a slower rate to indicate that the VTSS is armed. The security indicator continues flashing at the slower rate until the VTSS is disarmed or triggered. If the VTSS has alarmed and rearmed, the IPC will flash the security indicator at a steady, slow rate for about 30 seconds after the VTSS is disarmed.

- SKIS Indicator Lamp-On Message - Each time the IPC receives an electronic SKIS indicator lamp-ON message from the WIN, the security indicator will be illuminated. The indicator can be flashed ON and OFF, or illuminated solid, as dictated by the WIN message. The indicator remains illuminated solid or continues to flash until the IPC receives a lamp-OFF message from the WIN, or until the ignition switch is turned to the OFF position, whichever occurs first.

- Communication Error - If the IPC receives no lamp-ON or lamp-OFF messages from the WIN for 10 consecutive message cycles, the security indicator is illuminated by the instrument cluster. The indicator remains controlled and illuminated by the cluster until a valid lamp-ON or lamp-OFF message is received from the WIN.

The IPC controls the security indicator whenever the ignition switch is in the OFF position and the VTSS is arming, armed, or alarming. Whenever the ignition switch is in the ON or START positions, the WIN performs a self-test to decide whether the SKIS is in good operating condition and whether a valid key is present in the ignition lock cylinder. The WIN then sends the proper lamp-ON or lamp-OFF message to the IPC. If the IPC flashes the security indicator upon ignition ON, or turns ON the security indicator solid after the bulb test, it indicates that a SKIS malfunction has occurred or that the SKIS is ineffective.