Circuit/System Testing
WARNING: This page is about a different car, the 2017 Cadillac ATS. However, it is still accessible from the selected car via links, so may be relevant.
- Lighting components the vehicle is equipped with
- Each component's control and ground circuit terminals
- Component locations on the lighting control circuit
- Ignition OFF, scan tool disconnected, all doors closed, all accessories OFF, open and close drivers door, disconnect the harness connector at the component with inoperative dome/courtesy lamp. It may take up to 2 min for all vehicle systems to power down.
- Test for less than 10 Ω between the appropriate ground circuit terminal listed below and ground.
- E8D Door Courtesy Lamp - Driver terminal 2
- E8P Door Courtesy Lamp - Passenger terminal 2
- E8J Instrument Panel Courtesy Lamp - Left terminal 2
- E8K Instrument Panel Courtesy Lamp - Right terminal 2
- E37LF Dome/Reading Lamps - Left Front terminal 6
- E37RF Dome/Reading Lamps - Right Front terminal 6
- E37LR Dome/Reading Lamps - Left Rear terminal B (Sedan)
- E37RR Dome/Reading Lamps - Right Rear terminal B (Sedan)
- E37R Dome/Reading Lamps - Rear terminal 3 (Coupe)
- If 10 Ω or greater
- Ignition OFF.
- Test for less than 2 Ω in the ground circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, repair the open/high resistance in the ground connection.
- If less than 10 Ω
- Connect a test lamp between the appropriate control circuit terminal listed below and ground, ignition ON.
- E8D Door Courtesy Lamp - Driver terminal 1
- E8P Door Courtesy Lamp - Passenger terminal 1
- E8J Instrument Panel Courtesy Lamp - Left terminal 1
- E8K Instrument Panel Courtesy Lamp - Right terminal 1
- E37LF Dome/Reading Lamps - Left Front terminal 2
- E37RF Dome/Reading Lamps - Right Front terminal 2
- E37LR Dome/Reading Lamps - Left Rear terminal C (Sedan)
- E37RR Dome/Reading Lamps - Right Rear terminal C (Sedan)
- E37R Dome/Reading Lamps - Rear terminal 2 (Coupe)
- Verify the test lamp turns ON and OFF when commanding the Courtesy Lamps ON and OFF with a scan tool.
- If the test lamp is always OFF
- Ignition OFF, disconnect the X7 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.
- If the test lamp is always ON
- Ignition OFF, disconnect the X7 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.
- If the test lamp turns ON and OFF
- Test or replace the dome/courtesy lamp.
NOTE:
Each lighting component may need to be disconnected to isolate a short to ground. Use the schematics to identify the following: