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• | 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 |
---|---|---|---|---|
F5DR Fuse B+ | B270A 01 | B270A 01 | -- | -- |
Instrument Panel Dimmer Switch B+ Reference | B1395 03, B3600 03 | B3600 03 | 1 | B1395 07, 1 |
Instrument Panel Dimmer Switch Signal | B3600 03 | B3600 03 | B3600 07, 1 | - |
LED Backlight Dimming Control Terminal 8 X2 | B2610 02 | B2610 04, 1 | B2610 01, 1 | - |
LED Backlight Dimming Control Terminal 9 X7 | B2610 02 | B2610 04, 1 | B2610 01, 1 | - |
Garage Door Opener Switch Amber LED Control | B2625 02 | 2 | 2 | -- |
Vehicle ON/OFF Switch Dimming Control | 3 | 3 | 3 | -- |
Instrument Panel Dimmer Switch Low Reference | 1 | 1 | 1 | -- |
Charge Port Door Open Request Switch Ground | -- | 2 | -- | -- |
Dome/Reading Lamps - Front Ground | -- | 2 | -- | -- |
Driver Information Centre Switch Ground | -- | 2 | -- | -- |
Garage Door Opener Switch Ground | -- | 2 | -- | -- |
Multifunction Switch - Overhead Console Ground | -- | 2 | -- | -- |
Outside Wing Mirror Switch Ground | -- | 2 | -- | -- |
Hand Brake Control Switch Ground | -- | 2 | -- | -- |
Radio/HVAC Controls Ground | -- | 2 | -- | -- |
Refuel Request Switch Ground | -- | 2 | -- | -- |
Steering Wheel Controls Switch - Left Ground | -- | 2 | -- | -- |
Steering Wheel Controls Switch - Right Ground | -- | 2 | -- | -- |
Vehicle ON/OFF Switch Ground | -- | 3 | -- | -- |
1. Dimmer Switch Malfunction 2. Interior Backlighting Malfunction 3. Vehicle ON/OFF Switch Backlighting Malfunction |
The instrument panel dimmer switch is used to increase and decrease the brightness of the interior backlighting components. The instrument panel dimmer switch provides a voltage signal to the body control module (BCM) that will increase as the brightness of the lights are increased and decrease as the brightness of the lights are decreased. The BCM provides a low reference, signal, and B+ voltage reference circuits to the instrument panel dimmer switch. When the instrument panel dimmer switch is placed in the desired position, the dimmed voltage setting is applied from the instrument panel dimmer switch through the instrument panel dimmer switch signal circuit to the BCM. The BCM interprets the signal and applies a pulse width modulated (PWM) voltage through the light emitting diode (LED) dimming control circuits illuminating the interior backlighting to the requested level of brightness.
The instrument panel dimmer switch B+ reference circuit is a low current circuit that will not illuminate a test lamp.
Interior Lighting Systems Description and Operation
Control Module References for scan tool information
⇒ | If the reading does not change, refer to Dimmer Switch Malfunction. |
⇒ | If the backlighting components do not turn ON and OFF, refer to Interior Backlighting Malfunction. |
⇒ | If the vehicle ON/OFF switch backlighting does not change from low to high as the dimmer switch is operated or is always OFF, refer to Vehicle ON/OFF Switch Backlighting Malfunction. |
⇒ | If the test lamp does not illuminate, test the low reference circuit for a short to voltage or an open/high resistance. |
⇒ | If less than the specified range, test the B+ reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If the test lamp illuminates, test the B+ reference circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If less than the specified range, test the signal circuit terminal 10 for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If greater than the specified range, test the signal circuit terminal 10 for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
Note: Each component with backlighting may need to be disconnected to isolate a short to voltage or short to ground. Use the schematics to identify the following: • Backlighting components the vehicle is equipped with • Each components control and ground circuit terminals • Component locations on the backlighting control circuit
• | A20 Radio/HVAC Controls - terminal 17 |
• | S16 Driver Information Centre Switch - terminal 4 |
• | E37F Dome/Reading Lamps - Front - terminal 6 |
• | S25 Garage Door Opener - terminal 3 |
• | S48B Multifunction Switch - Overhead Console amber LED - terminal 6 |
• | S70R Steering Wheel Controls Switch - Right - terminal 5 |
• | S70L Steering Wheel Controls Switch - Left - terminal 7 |
• | S91 Hand Brake Control Switch - terminal 8 |
• | S48B Multifunction Switch - Overhead Console - terminal 2 |
• | S52 Outside Wing Mirror Switch - terminal 11 |
• | S113 Charge Port Door Open Request Switch - terminal 4 |
• | S117 Refuel Request Switch - terminal 4 |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
• | A20 Radio/HVAC Controls - terminal 18 |
• | S16 Driver Information Centre Switch - terminal 3 |
• | E37F Dome/Reading Lamps - Front - terminal 3 |
• | S25 Garage Door Opener - terminal 2 |
• | S48B Multifunction Switch - Overhead Console amber LED - terminal 3 |
• | S70L Steering Wheel Controls Switch - Left - terminal 6 |
• | S70R Steering Wheel Controls Switch - Right - terminal 4 |
• | S91 Hand Brake Control Switch - terminal 6 |
• | S48B Multifunction Switch - Overhead Console - terminal 1 |
• | S52 Outside Wing Mirror Switch - terminal 1 |
• | S113 Charge Port Door Open Request Switch - terminal 5 |
• | S117 Refuel Request Switch - terminal 5 |
⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp is always ON full intensity, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, programming and setup |
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