Circuit/System Testing

Ignition OFF, disconnect the harness connectors at the components listed below.
- S48E Multifunction Switch - Center Console
- S70L Steering Wheel Controls Switch - Left
Ignition ON, place the instrument panel dimmer switch in the HIGH position for high backlighting intensity.

NOTE:

The test lamp in the following step will illuminate at LOW intensity. This is normal circuit operation and does not indicate a circuit malfunction.

Verify a test lamp illuminates between each control circuit terminal listed below and ground.
- S48E Multifunction Switch - Center Console terminal 8
- S70L Steering Wheel Controls Switch - Left terminal 4
- If the test lamp does not illuminate
1. Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module.
2. 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
3. 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.
- 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 control circuit terminal listed below and ground.
- S48E Multifunction Switch - Center Console terminal 8
- S70L Steering Wheel Controls Switch - Left terminal 4
- If the test lamp illuminates at full intensity
1. Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module, ignition ON.
2. 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.
- If the test lamp does not illuminate at full intensity
Test or replace the component with the inoperative backlighting.