LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 2012 >> Regal Turbo, Automatic Trans >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Interior/Illumination Lights >> Lighting System >> Diagnostic Information and Procedures >> Front Fog Lamps Malfunction >> Circuit/System Testing

Circuit/System Testing

Front Fog Lamp Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Test for less than 30 Ω between the ground circuit terminal 6 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. Ignition ON, test for less than 0.3 V between signal circuit terminal 12 and ground.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the B+ circuit terminal 1. The interior backlighting should be dimmed.
    • If the interior backlighting is not dimmed, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. If all circuits test normal, test or replace the S30 headlamp switch.

Front Fog Lamps Malfunction

  1. Ignition OFF, disconnect the X2 harness connector at the X50A underhood fuse block.
  2. Connect a test lamp between the control circuit terminal 19 and B+.
  3. Command the Front Fog Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    • If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM.
    • If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. Ignition OFF, connect the X2 harness connector at the X50A underhood fuse block. Disconnect the harness connector at the E29 fog lamp-front.
  5. Test for less than 30 Ω between the ground circuit terminal 2 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Connect a test lamp between the control circuit terminal 1 and ground.
  7. Ignition ON, command the Fog Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    • If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the X50A underhood fuse block.
    • If the test lamp is always OFF and the circuit fuse is good, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the X50A underhood fuse block.
    • If the test lamp is always OFF and the circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test or replace the E29 fog lamp-front.
  8. If all circuits test normal, test or replace the E29 fog lamp-front.
scientia non olet · About LEMON Manuals