GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Park Avenue 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Daytime Running Lamps (DRL) Headlamps Inoperative

Step

Action

Value(s)

Yes

No

1

Did you perform the Headlights System Check?

--

Go to Step 2

Go to Headlight System Check

2
  1. Disconnect the Lamp Control Module (LCM) connector C2.
  2. Cover the ambient light sensor.
  3. Connect a DMM from the LCM connector C2 terminal A5 (WHT) to ground.

Is the resistance greater than the specified value?

31K ohms

Go to Step 3

Go to Step 11

3
  1. Expose the ambient light sensor to a bright incandescent light.
  2. Connect a DMM from the LCM connector C2 terminal A5 (WHT) to ground.

Is the resistance less than the specified value?

23K ohms

Go to Step 4

Go to Step 11

4
  1. Turn the ignition switch to the RUN position.
  2. Connect a DMM from the LCM connector C2 terminal A7 (PNK) to ground.

Is the voltage within the specified range?

10-15 V

Go to Step 5

Go to Step 14

5
  1. Connect a DMM from the LCM connector C2 terminal A8 (LT GRN) to ground.
  2. Place the gear selector in the PARK position.

Is the voltage within the specified range?

10-15 V

Go to Step 6

Go to Step 15

6
  1. Disconnect the LCM connector C1.
  2. Connect a fused jumper from the LCM connector C1 cavity G (RED) to cavity D (DK BLU).

Do the high beam headlamps light at a reduced intensity?

--

Go to Step 10

Go to Step 7

7

Inspect CKT 593 (DK BLU) between the LCM and the LH high beam headlamp for an open or a short to ground. Refer to Testing for Short to Ground or Testing for Continuity in Wiring Systems.

Is CKT 593 OK?

--

Go to Step 8

Go to Step 18

8

Inspect CKT 711 (DK GRN/WHT) between the underhood fuse block and the LH high beam headlamp for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 711 OK?

--

Go to Step 9

Go to Step 18

9

Inspect CKT 311 (LT GRN) between the underhood fuse block and the RH high beam headlamp for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 311 OK?

--

Go to Step 17

Go to Step 18

10

Replace the LCM. Refer to Lamp Control Module Replacement .

Is the repair complete?

--

Go to Headlight System Check

--

11

Inspect for a short to ground or an open in CKT 278 (WHT). Refer to Testing for Short to Ground or Testing for Continuity in Wiring Systems.

Is CKT 278 OK?

--

Go to Step 12

Go to Step 18

12

Inspect for an open in CKT 351 (BLK/WHT) between the ambient light sensor and S213. Refer to Testing for Continuity in Wiring Systems.

Is CKT 351 OK?

--

Go to Step 13

Go to Step 18

13

Replace the ambient light sensor. Refer to Defroster Grille Replacement in Instrument Panel, Gauges and Console.

Is the repair complete?

--

Go to Headlight System Check

--

14

Repair the open in CKT 39 (PNK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

15

Inspect for an open in CKT 275 (LT GRN) between the Body Control Module (SBM) and the LCM. Refer to Testing for Continuity in Wiring Systems.

Is CKT 275 OK?

--

Go to Step 16

Go to Step 18

16

Replace the LCM. Refer to Lamp Control Module Replacement .

Is the repair complete?

--

Go to Headlight System Check

--

17

Repair the open in CKT 250 (BLK) between the RH high beam headlamp and S101. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

18

Repair the faulty wiring. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--