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Circuit/System Testing

WARNING: This page is about a different car, the 2021 Buick Enclave. However, it is still accessible from the selected car via links, so may be relevant.
    NOTE:

    Each component may need to be disconnected to isolate a short to voltage, short to ground, or an open/high resistance. Use the schematics to identify the following:

    • Courtesy lamps the vehicle is equipped with
    • Each component's control and ground circuit terminals
    • Component locations on the exterior courtesy lamps control circuit
  1. Ignition OFF, scan tool disconnected, all doors closed, all accessories OFF, open and close drivers door, disconnect the harness connector at the inoperative accent/flood lamp. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the appropriate ground circuit terminal and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. 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.
    • Go to next step: If less than 10 Ω 
  3. Connect a test lamp between the appropriate control circuit terminal and ground, ignition ON.
  4. Verify the test lamp turns ON and OFF when commanding the Accent Lighting 1 ON and OFF with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, disconnect the X6 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.
      • Go to next step: 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 is always ON 
    1. Ignition OFF, disconnect the X6 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.
    • Go to next step: If the test lamp turns ON and OFF 
  5. Test or replace the accent/flood lamp.
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