Headlamps Inoperative - Low Beams
WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
Headlamps Inoperative - Low Beams
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics Connector End View Reference: Master Electrical Component List in Wiring Systems |
|||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Turn ON the headlamps. Do both low beam headlamps illuminate? |
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
| 3 | Is only one low beam headlamp inoperative? | Go to Step 8 | Go to Step 4 |
| 4 | Are the park lamps ON? | Go to Step 5 | Go to Step 6 |
| 5 |
|
Go to Step 11 | Go to Step 13 |
| 6 | Using a scan tool, observe the Low Beam Switch Input parameter. Does the parameter indicate ON? |
Go to Step 12 | Go to Step 7 |
| 7 | Test the headlamp switch headlamps ON signal and the ground circuit of the headlamp switch for the following:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? |
Go to Step 18 | Go to Step 10 |
| 8 | Test the low beam headlamp voltage supply and ground circuits of the inoperative headlamp for the following:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? |
Go to Step 18 | Go to Step 9 |
| 9 | Inspect for a poor connections at the harness connector of the inoperative headlamp. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 18 | Go to Step 14 |
| 10 | Inspect for a poor connections at the harness connector of the headlamp switch. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 18 | Go to Step 15 |
| 11 | Inspect for a poor connections at the harness connector of the low beam relay. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 18 | Go to Step 16 |
| 12 | Inspect for a poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 18 | Go to Step 17 |
| 13 |
IMPORTANT:
The BCM may need to be reset if a short to voltage is repaired. To reset the BCM, remove the STOP/TURN and the CHMSL/BACKUP fuses in the instrument panel (I/P) fuse panel for 10 seconds. with the ignition key in the OFF position. Repair the low beam relay control circuit of the BCM for the following:
|
Go to Step 18 | - |
| 14 | Replace the inoperative low beam headlamp. Refer to Headlamp Assembly or Headlamp Bulb Replacement . Did you complete the replacement? |
Go to Step 18 | - |
| 15 | Replace the headlamp switch. Refer to Headlamp Switch Replacement . Did you complete the replacement? |
Go to Step 18 | - |
| 16 | Replace the low beam relay. Refer to Relay Replacement (Within an Electrical Center)
or Relay Replacement (Attached to Wire Harness)
in Wiring Systems. Did you complete the replacement? |
Go to Step 18 | - |
| 17 | Replace the BCM. Refer to Control Module References
in Computer/Integrating Systems for replacement, setup and programming. Did you complete the replacement? |
Go to Step 18 | - |
| 18 | Operate the system in order to verify the repair. Did you correct the condition? |
System OK | Go to Step 3 |