• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
B+, BCM C2 Terminal 2 | B2652 00 | B2652 00 | -- | -- |
B+, BCM C3 Terminal 2 | 1 | 1 | -- | -- |
I/P Dimming Voltage Reference | B1395 03, B3600 03 | B3600 03 | 1, 2 | -- |
Backlight Lamp Control | B2610 00 | 1 | 1 | -- |
Driver Heated and Cooled Seat Switch Lamp Dimming | 3 | 3 | 3 | -- |
Passenger Heated and Cooled Seat Switch Lamp Dimming | 3 | 3 | 3 | -- |
Instrument Panel Lamps Dimmer Switch Signal | B3600 03 | B3600 03 | 1, 2 | -- |
Instrument Panel Lamp Supply Voltage | B2652 00 | 1 | 1 | -- |
LED Dimming Supply | B2610 00 | 2 | 2 | -- |
Headlamp Switch Ground | -- | 2 | -- | -- |
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The BCM supplies a voltage reference through the instrument panel (I/P) dimming voltage reference circuit to the interior lamp dimmer switch, which is part of the headlamp switch. When the dimmer switch is placed in a desired brightness position, reference voltage is applied through the dimmer switch rheostat and the I/P lamps dimmer switch signal circuit to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage through the instrument panel lamp supply voltage circuit and the LED dimming supply circuit illuminating the LED and I/P panel lamps. For more detailed information concerning interior lamp operation refer to Interior Lighting Systems Description and Operation.
Interior Lights Dimming Schematics
Lighting Systems Connector End Views
⇒ | If the backlighting does not turn On and OFF or remains always ON, replace the driver door switch. |
⇒ | If the backlighting does not turn On and OFF or remains always ON, refer to Front Door Switch Backlighting Circuit Test. |
⇒ | If the backlighting does not turn On and OFF or always remains ON, replace the passenger door switch. |
⇒ | If the backlighting does not turn On and OFF or remains always ON, refer to Front Door Switch Backlighting Circuit Test. |
⇒ | If the reading does not change, refer to Dimmer Switch Circuit Test. |
⇒ | If the scan tool dimmer control operates normal, refer to Interior Backlighting Circuit Test. |
⇒ | If the test lamp does not illuminate, test the ground circuit for an open/high resistance. |
⇒ | If greater than the specified range, test the signal circuit terminal 13 for a short to voltage. If the circuit tests normal, replace the BCM. |
⇒ | If less than the specified value, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
• | Headlamp Switch terminal 8 |
• | Hazard Switch terminal B |
• | Instrument Panel Cluster (IPC) terminal 6 |
• | Ashtray Lamp terminal B |
• | HVAC Control Module terminal 11 C1 |
• | Radio terminal 8 C1 |
• | Driver Information Display Switch terminal 5 |
• | Traction Control Switch terminal A |
• | Reverse Lockout Solenoid terminal D C2 |
• | Garage Door Opener Transmitter terminal 3 |
• | Sunroof Switch terminal 5 |
• | Left Rear Door Window Switch terminal F |
• | Right Rear Door Window Switch terminal F |
• | Right Steering Wheel Control Switch terminal 1 |
• | Left Steering Wheel Control Switch terminal 8 |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
• | Headlamp Switch terminal 7 |
• | Hazard Switch terminal A |
• | Instrument Panel Cluster (IPC) terminal 8 |
• | Ashtray Lamp terminal A |
• | Traction Control Switch terminal D |
• | Reverse Lockout Solenoid terminal C C2 |
• | Garage Door Opener Transmitter terminal 2 |
• | Sunroof Switch terminal 3 |
• | Left Rear Door Window Switch terminal B |
• | Right Rear Door Window Switch terminal B |
• | HVAC Control Module terminal 2 with C67 C2 or CJ2 C3 |
• | Radio terminal 7 C1 |
• | Driver Information Display Switch terminal 4 |
• | Right Steering Wheel Control Switch terminal 2 |
• | Left Steering Wheel Control Switch terminal 6 |
⇒ | If the test lamp is always OFF, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM |
⇒ | If the test lamp is always ON, test the supply voltage circuit for a short to voltage. If the circuit tests normal, replace the BCM. |
• | Driver Heated and Cool Seat Switch terminal 3 |
• | Passenger Heated and Cool Seat Switch terminal 5 |
⇒ | If the test lamp does not illuminate, test the low reference circuit for an open/high resistance. |
• | Driver Heated and Cool Seat Switch terminal 5 |
• | Passenger Heated and Cool Seat Switch terminal 3 |
⇒ | If the test lamp is always OFF, test the dimming control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the door switch. |
⇒ | If the test lamp is always ON, test the dimming control circuit for a short to voltage. If the circuit tests normal, replace the door switch. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM, HVAC, IPC, or Radio replacement, setup, and programming |