Circuit/System Testing
- Backlighting components the vehicle is equipped with
- Each component's control and ground circuit terminals
- Component locations on the backlighting control circuit
- Ignition OFF, disconnect the harness connector at the appropriate switch listed below.
- A98 Front Overhead Console Assembly
- S48E Multifunction Switch - Center Console (Chevrolet)
- S126 Drive Mode Select Switch (GMC)
- S107 Parking Assist On/Off Switch (UFQ)
- S13D Door Lock Switch - Driver
- S13P Door Lock Switch - Passenger
- Ignition ON, place the instrument panel dimmer switch in the HIGH position for high backlighting intensity.
- Verify a test lamp illuminates between the appropriate control circuit terminal listed below and ground.
- A98 Front Overhead Console Assembly terminal 18
- S48E Multifunction Switch - Center Console terminal 5 (Chevrolet)
- S126 Drive Mode Select Switch terminal 8 (GMC)
- S107 Parking Assist On/Off Switch terminal 5 (UFQ)
- S13D Door Lock Switch - Driver terminal 5
- S13P Door Lock Switch - Passenger terminal 5
- If the test lamp does not illuminate
- Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module.
- Test for infinite resistance between the control circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the control circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K9 Body Control Module.
- Go to next step: If the test lamp illuminates
- Place the instrument panel dimmer switch in the LOW position for low backlighting intensity.
- Verify a test lamp does not illuminate at FULL intensity between the appropriate control circuit terminal listed below and ground.
- A98 Front Overhead Console Assembly terminal 18
- S48E Multifunction Switch - Center Console terminal 5 (Chevrolet)
- S126 Drive Mode Select Switch terminal 8 (GMC)
- S107 Parking Assist On/Off Switch terminal 5 (UFQ)
- S13D Door Lock Switch - Driver terminal 5
- S13P Door Lock Switch - Passenger terminal 5
- If the test lamp illuminates at full intensity
- Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module, ignition ON.
- Test for less than 1 V between the control circuit terminal and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K9 Body Control Module.
- Go to next step: If the test lamp does not illuminate at full intensity
- Test or replace the inoperative component.
NOTE:
Each component with backlighting may need to be disconnected to isolate a short to voltage or short to ground. Use the wiring schematics to identify the following: