For 1990-2009 cars

## Incandescent Lamps Inoperative Buick

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: This table diagnoses inoperative incandescent lamps. It assumes that all vacuum fluorescent (VF) displays operate properly.
1 | Did you perform the Interior Lights Dimming System Check? | -- | Go to Step 2 | Go to Interior Lights Dimming System Check
2 |

1. Place the headlamp switch in the PARK position.
2. Backprobe the lamp dimmer switch connector with a DMM from cavity J (ORN) to ground.

Is the voltage within the specified range?

10-15V

Go to Step 3

Go to Step 9

3 | Backprobe the lamp dimmer switch connector with a DMM from cavity C (YEL) to ground. Is the voltage within the specified range? | 10-15V | Go to Step 4 | Go to Step 10
4 | Backprobe the lamp dimmer switch connector with a DMM from cavity J (ORN) to G (BLK/WHT). Is the voltage within the specified range? | 10-15V | Go to Step 5 | Go to Step 11
5 | Backprobe the remote dimmer module connector with a DMM from cavity D (YEL) to ground. Is the voltage within the specified range? | 10-15V | Go to Step 6 | Go to Step 13
6 |

1. Backprobe the remote dimmer module connector with a DMM from cavity B (DK GRN) to ground.
2. Slowly adjust the lamp dimmer switch between LO and HI.

Does the voltage vary while adjusting the lamp dimmer switch?

--

Go to Step 7

Go to Step 14

7 |

1. Disconnect the remote dimmer module connector.
2. Connect a fused jumper from the remote dimmer module connector cavity D (YEL) to C (GRY).

Do all of the incandescent lights light at the full intensity?

--

Go to Step 8

Go to Step 16

8 | Replace the remote dimmer module. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
9 | Repair the open in CKT 40 (ORN) between S214 and the lamp dimmer switch. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
10 | Repair the open in CKT 32 (YEL) between S234 and the lamp dimmer switch. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
11 | Inspect for an open in CKT 251 (BLK/WHT) between the lamp dimmer switch and the lamp control module (LCM). Refer to Testing for Continuity in Wiring Systems. Is CKT 251 OK? | -- | Go to Step 12 | Go to Step 17
12 | Replace the LCM. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
13 | Repair the open in CKT 32 (YEL) between S234 and the remote dimmer module. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
14 | Inspect for an open in CKT 44 (DK GRN) between the lamp dimmer switch and the remote dimmer module. Refer to Testing for Continuity in Wiring Systems. Is CKT 44 OK? | -- | Go to Step 15 | Go to Step 17
15 | Replace the lamp dimmer switch. Refer to Instrument Panel Multifunction Switch Assembly Replacement in Instrument Panel, Gauges and Console. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
16 | Repair the open in CKT 8 (GRY) between S291 and the remote dimmer module. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
17 | Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --

## Incandescent Lamps Inoperative Oldsmobile

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: This table diagnoses inoperative incandescent lamps. It assumes that all vacuum fluorescent (VF) displays operate properly.
1 | Did you perform the Interior Lights Dimming System Check? | -- | Go to Step 2 | Go to Interior Lights Dimming System Check
2 |

1. Place the headlamp switch in the PARK position.
2. Backprobe the interior lamp control module connector with a DMM from cavity H (YEL) to ground.

Is the voltage within the specified range?

10-15V

Go to Step 3

Go to Step 8

3 | Backprobe the interior lamp control module connector with a DMM from cavity H (YEL) to cavity K (BLK/WHT). Is the voltage within the specified range? | 10-15V | Go to Step 4 | Go to Step 9
4 | Backprobe the interior lamp control module connector with a DMM from cavity H (YEL) to the headlamp switch terminal N (BLK). Is the voltage within the specified range? | 10-15V | Go to Step 5 | Go to Step 10
5 |

1. Disconnect the interior lamp control module connector.
2. Connect a DMM from the interior lamp control module connector cavity D (DK GRN) to ground.
3. Slowly rotate the interior dimming switch in both directions.

Does the resistance vary with the control of the interior dimming switch?

--

Go to Step 11

Go to Step 6

6 | Inspect for an open or short to ground in CKT 44 (DK GRN) between the headlamp switch and the interior lamp control module. Refer to Testing for Continuity or Testing for Short to Ground in Wiring Systems. Is CKT 44 OK? | -- | Go to Step 7 | Go to Step 13
7 | Replace the headlamp switch. Refer to Instrument Cluster Trim Panel Replacement in Instrument Panel, Gauges and Console. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
8 | Repair the open in CKT 32 (YEL) between S234 and the interior lamp control module. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
9 | Repair the open in CKT 251 (BLK/WHT) between the interior lamp control module and S249. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
10 | Repair the open in CKT 1250 (BLK) between the headlamp switch and S213. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
11 | Inspect for an open in CKT 8 (GRY) between the interior lamp control module and S291. Refer to Testing for Continuity in Wiring Systems. Is CKT 8 OK? | -- | Go to Step 12 | Go to Step 13
12 | Replace the interior lamp control module. Refer to Instrument Panel Knee Bolster in Instrument Panel, Gauges and Console. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
13 | Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --

## Incandescent Lamps Inoperative Pontiac

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: This table diagnoses inoperative incandescent lamps. It assumes that all vacuum fluorescent (VF) displays operate properly.
1 | Did you perform the Interior Lights Dimming System Check? | -- | Go to Step 2 | Go to Interior Lights Dimming System Check
2 |

1. Place the headlamp switch in the PARK position.
2. Backprobe the headlamp switch connector with a DMM from cavity S (YEL) to ground.

Is the voltage within the specified range?

10-15V

Go to Step 3

Go to Step 5

3 |

1. Disconnect the headlamp switch connector.
2. Connect a fused jumper from the headlamp switch connector cavity S (YEL) to J (GRY).

Do all of the incandescent lights light at the full intensity?

--

Go to Step 4

Go to Step 6

4 | Replace the headlamp switch. Refer to Instrument Cluster Trim Panel Replacement in Instrument Panel, Gauges and Console. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
5 | Repair the open in CKT 32 (YEL) between S234 and the headlamp switch. Refer to Wiring Repairs in Wiring Repairs. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
6 | Inspect for an open in CKT 8 (GRY) between S291 and the headlamp switch. Refer to Testing for Continuity in Wiring Repairs. Is CKT 8 OK? | -- | Go to Step 7 | Go to Step 8
7 | Repair the open in CKT 1250 (BLK) between S213 and S225. Refer to Wiring Repairs in Wiring Repairs. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --
8 | Repair the open in CKT 8 (GRY) between S291 and the headlamp switch. Refer to Wiring Repairs in Wiring Repairs. Is the repair complete? | -- | Go to Interior Lights Dimming System Check | --