LEMON Manuals: Even more car manuals for everyone
Home >> Hummer >> 2008 >> H3 Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 264 (Lighting Systems) >> Diagnostic Information and Procedures >> Cargo Lamps Malfunction >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different car, the 2009 GMC Canyon and 2009 Chevrolet Colorado. However, it is still accessible from the selected car via links, so may be relevant.

Cargo Lamp Switch Malfunction

  1. Ignition OFF, disconnect the headlamp and panel dimmer switch connector.
  2. Test for less than 5 ohms between the low reference circuit terminal 3 and ground.
    • If greater than the specified range, test the low reference circuit for an open/high resistance.
  3. Ignition ON, verify that the scan tool Cargo Lamp Switch parameter displays Inactive.
    • If the parameter displays Active test the control circuit terminal 10 for a short to ground. If the circuit tests normal, replace the BCM.
  4. Install a 3A fused jumper wire between the control circuit terminal 10 and the ground circuit terminal 3. Verify the scan tool Cargo Lamp Switch parameter displays Active.
    • If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  5. If the circuits test normal, test or replace the headlamp and panel dimmer switch.

Cargo Lamp Malfunction

  1. Ignition OFF, disconnect the harness connector at the inoperative cargo lamp bulb.
  2. Test for less than 5 ohms between the ground circuit terminal B and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal A and the ground circuit terminal B.
  4. Command the Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF.
    • If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
    • If the test lamp is always OFF, test the control circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the BCM.
  5. If all circuits test normal, test or replace the inoperative bulb.
scientia non olet · About LEMON Manuals