Fog Lamps Always On V6
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Fog Lights Schematics Connector End View Reference: Master Electrical Component List | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 |
Do the fog lamps remain illuminated? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections |
3 | Disconnect the fog lamp relay. Did the fog lamps turn off? | Go to Step 4 | Go to Step 8 |
4 |
Do the fog lamps remain illuminated? | Go to Step 5 | Go to Step 10 |
5 | Disconnect the body control module (BCM) connector C3. Do the fog lamps remain illuminated? | Go to Step 6 | Go to Step 9 |
6 | Disconnect the BCM connector C1. Do the fog lamps remain illuminated? | Go to Step 7 | Go to Step 12 |
7 | Test for a short to ground in the fog lamp relay control circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 11 |
8 | Repair a short to battery positive voltage in the fog lamp voltage supply circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair? | Go to Step 13 | -- |
9 | Repair a short to ground in the fog lamp switch signal circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair? | Go to Step 13 | -- |
10 | Replace the multifunction turn signal switch. Refer to Turn Signal Multifunction Switch Replacement . Did you complete the repair? | Go to Step 13 | -- |
11 | Replace the fog lamp relay. Refer to Relay Replacement . Did you complete the replacement? | Go to Step 13 | -- |
12 | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 13 | -- |
13 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
Fog Lamps Always On V8
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Front Fog Lamp Control Circuit | 2 | 1 | B2530 | -- |
| ||||
Circuit/System Description
Voltage is applied at all times to the fog lamp relay. When the fog lamp switch is placed in the ON position, ground is applied to the body control module (BCM) through the fog lamp switch circuit. The BCM then applies a ground to the front fog lamp control circuit. This engages the fog lamp relay and applies voltage through the fog lamp fuse to the front fog lamps.
Reference Information
Schematic Reference
Connector End View Reference
Lighting Systems Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
- Ignition ON, turn the park lamps ON. Press the front fog lamp switch. The front fog lamps should illuminate.
- Observe the scan tool front fog lamps switch parameter while pressing the fog lamp switch. The reading should change between ON and OFF.
| ⇒ | If the for lamps do not illuminate and the fog lamp switch parameter does not change between ON and OFF when pressing the fog lamp switch--Test input side of BCM for inoperative condition in Circuit/System Testing. |
| ⇒ | If the for lamps do not illuminate and the fog lamp switch parameter does change between ON and OFF when pressing the fog lamp switch--Test output side of BCM for inoperative condition in Circuit/System Testing. |
Circuit/System Testing
Test Input Side of BCM For Inoperative Fog Lamps
- Ignition OFF, disconnect the malfunction turn signal lever harness connector at the switch.
- Test for less than 1 ohm of resistance between the ground circuit terminal 3 and ground.
- Ignition ON, verify the scan tool front fog lamp switch parameter displays OFF.
- Install a 3A fused jumper wire between the signal circuit terminal 4 and the ground circuit terminal 3. Verify the scan tool front fog lamp switch parameter displays closed.
- If all circuits test normal, test or replace the multifunction turn signal lever.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the body control module. |
| ⇒ | 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 body control module. |
Test Output Side of BCM For Inoperative Fog Lamps
- Disconnect the harness connector at both fog lamps.
- Test for less than 1.0 ohm of resistance between the appropriate fog lamp ground circuit terminal B and ground.
- Connect a test lamp between the control circuit terminal A and ground.
- 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 all circuits test normal, replace the appropriate fog lamp bulb socket.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BEC. |
| ⇒ | 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 BEC. |
| ⇒ | 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, replace the appropriate fog lamp bulb socket. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
