For 1990-2009 cars

## Headlamps Inoperative - High Beams Pontiac

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 | Operate the headlamp dimmer switch in the HIGH and LOW positions. Do the low beam headlamps operate? | -- | Go to Step 6 | Go to Step 3
3 | Backprobe the headlamp switch connector with a test lamp from cavity A (RED) to ground. Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 10
4 |

1. Disconnect the headlamp switch connector.
2. Connect a fused jumper from the headlamp switch cavity A (RED) to cavity D (YEL).

Do the high beam headlamps illuminate?

--

Go to Step 11

Go to Step 5

5 |

1. Leave the jumper in place.
2. Use a test lamp in order to backprobe the headlamp dimmer switch connector C202 from cavity C5 (YEL) to ground.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 12

6 |

1. Reconnect the headlamp switch
2. Disconnect the headlamp dimmer switch
3. Connect a fused jumper from the headlamp dimmer switch connector C202 cavity C5 (YEL) to B5 (LT GRN).

Do the high beams illuminate?

--

Go to Step 14

Go to Step 7

7 | Is the vehicle equipped with lamp monitoring? | -- | Go to Step 8 | Go to Step 13
8 |

1. Disconnect the adaptive lamp monitor control module connectors C1 and C2.
2. Connect a fused jumper from the adaptive lamp monitor control monitor connector C@ cavity A (LT GRN) to connector C1 Cavity R (LT GRN).
3. Place the headlamp dimmer switch in the HIGH position.

Do the high beam headlamps illuminate?

--

Go to Step 9

Go to Step 15

9 | Replace the lamp monitor control module. Refer to Instrument Panel Lamp Dimmer Replacement in Instrument Panel, Gauges, and Console. Is the replacement complete? | -- | Go to Headlight System Check | --
10 | Repair the open in CKT 242 (RED) between S201 and the headlamp switch. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
11 | Replace the headlamp switch. Refer to Instrument Cluster Trim Panel Replacement in Instrument Panel, Gauges and Console. Is the replacement complete? | -- | Go to Headlight System Check | --
12 | Repair the open in CKT 10 (YEL) between the headlamp switch and the headlamp dimmer switch connector C202. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
13 | Inspect CKT 11 (LT GRN) between the headlamp dimmer switch C202 and S245 for and open. Refer to Wiring Repairs in Wiring Systems. Is CKT 11 (LT GRN) OK? | -- | Go to Step 14 | Go to Step 17
14 | Replace the headlamp dimmer switch. Refer to Dimmer Switch Assembly - Disassemble - Off Vehicle and Dimmer Switch Assembly - Assemble - Off Vehicle in Steering Wheel and Column-Tilt. Is the replacement complete? | -- | Go to Headlight System Check | --
15 | Inspect CKT 11 (LT GRN) for an open between the headlamp dimmer switch connector C202 and the adaptive lamp monitor control module. Refer to Wiring Repairs in Wiring Systems. Is CKT 11 (LT GRN) OK? | -- | Go to Step 16 | Go to Step 17
16 | Inspect CKT 1311 (LT GRN) for and open between the adaptive lamp monitor control module and S259. Refer to Wiring Repairs in Wiring Systems. Is CKT 1311 (LT GRN) OK? | -- | Go to Step 14 | Go to Step 17
17 | 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 |

1. Disconnect the lamp control module (LCM) connector C1.
2. Connect a DMM from the LCM connector C1 cavity E (RED) to ground.

Is the voltage within the specified range?

10-15V

Go to Step 3

Go to Step 9

3 | Use a test lamp in order to backprobe the headlamp switch connector from cavity D (RED) to ground. Does the test lamp light? | -- | Go to Step 4 | Go to Step 10
4 |

1. Remove the headlamp relay (position J) from the RH IP fuse block.
2. Connect a DMM from the headlamp relay (position J) cavity 30 (RED) to ground.

Is the voltage within the specified range?

10-15V

Go to Step 5

Go to Step 11

5 |

1. Place the headlamp switch in the HEAD position.
2. Connect a DMM from the headlamp relay (position J) cavity 85 (YEL) to ground.

Is the voltage within the specified range?

10-15V

Go to Step 6

Go to Step 12

6 | Connect a DMM from the headlamp relay (position J) cavity 30 (RED) to cavity 86 (BLK). Is the voltage within the specified range? | 10-15V | Go to Step 7 | Go to Step 14
7 | Connect a fused jumper from the headlamp relay (position J) cavity 30 (RED) to cavity 87 (LT BLU). Do the high beam headlamps light? | -- | Go to Step 15 | Go to Step 8
8 |

1. Leave the fused jumper in place.
2. Use a test lamp in order to backprobe the headlamp dimmer switch connector C202 from cavity C5 (LT BLU) to ground.

Does the test lamp light?

--

Go to Step 17

Go to Step 16

9 | Repair the open in CKT 242 (RED) between S201 and the LCM. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
10 | Repair the open in CKT 242 (RED) between S201 and the headlamp switch. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
11 | Repair the open in CKT 242 (RED) between S201 and the RH IP fuse block. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
12 | Inspect CKT 10 (YEL) for an open between the headlamp switch and the RH IP fuse block. Refer to Testing for Continuity in Wiring Systems. Is CKT 10 (YEL) OK? | -- | Go to Step 13 | Go to Step 19
13 | Replace the headlamp switch.

• | For Pontiac only, refer to Instrument Cluster Trim Panel Replacement in Instrument Panel, Gauges and Console.

• | For Oldsmobile only, refer to Instrument Cluster Trim Panel Replacement in Instrument Panel, Gauges and Console.

• | For Pontiac only, refer to Instrument Cluster Trim Panel Replacement in Instrument Panel, Gauges and Console.

Is the repair complete?

--

Go to Headlight System Check

--

14 | Repair the open in CKT 1450 (BLK) between the RH IP fuse block and S308. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
15 | Replace the headlamp relay (position J) in the RH IP junction block. Is the repair complete? | -- | Go to Headlight System Check | --
16 | Repair the open in CKT 1346 (LT BLU) between the RH IP fuse block and the headlamp dimmer switch connector C202. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
17 | Inspect CKT 11 (LT GRN) for an open between the headlamp dimmer switch connector C202 and S245. Refer to Testing for Continuity in Wiring Systems. Is CKT 11 (LT GRN) OK? | -- | Go to Step 18 | Go to Step 19
18 | Replace the headlamp dimmer switch. Refer to Dimmer Switch Assembly - Disassemble - Off Vehicle or Dimmer Switch Assembly - Assemble - Off Vehicle in Steering and Column-Tilt. Is the replacement complete? | -- | Go to Headlight System Check | --
19 | Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --

## 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 B5 (PPL) to ground.

Do the headlamps change from low beams to high beams?

--

Go to Step 5

Go to Step 3

3 |

1. Disconnect the lamp control module (LCM) connector C1.
2. Connect a fused jumper from the LCM connector C1 cavity G (RED) to cavity B (LT GRN).

Do the high beam headlamps light?

--

Go to Step 7

Go to Step 4

4 | Repair the open in CKT 11 (LT GRN). Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Headlight System Check | --
5 | Inspect for an open in CKT 251 (BLK/WHT) between the headlamp dimmer switch connector C202 and S293. Refer to Testing for Continuity in Wiring Systems. Is CKT 251 OK? | -- | Go to Step 6 | Go to Step 9
6 | Replace the headlamp dimmer switch. Refer to Dimmer Switch Assembly - Disassemble - Off Vehicle and Dimmer Switch Assembly - Assemble - Off 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 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 | --