For 1990-2009 cars

## Headlamps Inoperative - High Beams Buick

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the entire headlights system check? | -- | Go to Step 2 | Go to Headlight System Check
2 |

1. Disconnect the headlamp dimmer switch connector C202.
2. Place the headlamp switch in the ON position.
3. Connect a fused jumper from the headlamp dimmer switch connector C202 cavity E13 (PPL) to ground.

Do the headlights switch from low beams to high beams?

--

Go to Step 5

Go to Step 3

3 |

1. Disconnect the lamp control module (LCM) connector C2.
2. Connect a fused jumper from the LCM connector C2 cavity G (ORN) to cavity B (LT GRN).

Do the high beam headlights light?

--

Go to Step 7

Go to Step 4

4 | Repair the open in CKT 11 (LT GRN) between the LCM and S142. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
5 | Inspect for an open in CKT 351 (BLK/WHT) between S263 and the headlamp dimmer switch connector C202. Refer to Testing for Continuity in Wiring Systems. Is CKT 351 OK? | -- | Go to Step 6 | Go to Step 9
6 | Replace the headlamp dimmer switch. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column - Tilt. Is the repair complete? | -- | Go to Headlight System Check | --
7 | Inspect for an open in CKT 524 (PPL) between the LCM and the headlamp dimmer switch connector C202. Refer to Testing for Continuity in Wiring Systems. Is CKT 524 OK? | -- | Go to Step 8 | Go to Step 9
8 | Replace the lamp control module (LCM). Is the repair complete? | -- | Go to Headlight System Check | --
9 | Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --

## Headlamps Inoperative - High Beams Oldsmobile

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the entire headlights system check? | -- | Go to Step 2 | Go to Headlight System Check
2 | Backprobe the headlamp dimmer switch connector C202 with a DMM from cavity E10 (RED) to ground. Is the voltage within the specified range? | 10-15V | Go to Step 3 | Go to Step 5
3 |

1. Disconnect the headlamp dimmer switch connector C202.
2. Connect a fused jumper from the headlamp dimmer switch connector C202 cavity E10 (RED) to cavity E11 (LT GRN).

Do the high beam headlights light?

--

Go to Step 4

Go to Step 6

4 | Replace the headlamp dimmer switch. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column - Tilt. Is the repair complete? | -- | Go to Headlight System Check | --
5 | Repair the open in CKT 42 (RED) between S221 and the headlamp dimmer switch connector C202. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
6 | Repair the open in CKT 11 (LT GRN) between the headlamp dimmer switch connector C202 and S142. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --