GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Park Avenue 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Headlamps Inoperative - Low Beams

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 C1.
  2. Connect a DMM from the LCM connector C1 cavity G (RED) to ground.

Is the voltage within the specified range?

10-15 V

Go to Step 3

Go to Step 8

3
  1. Disconnect the LCM connector C2.
  2. Connect a DMM from the LCM connector C1 cavity G to connector C2 cavity B4 (BLK/WHT).
  3. Connect a DMM from the LCM connector C1 cavity G (RED) to connector C2 cavity B5 (BLK/WHT).

Is the voltage within the specified range for each test?

10-15 V

Go to Step 4

Go to Step 9

4

Connect a DMM from the LCM connector C1 cavity G (RED) to cavity E (BLK).

Is the voltage within the specified range?

10-15 V

Go to Step 5

Go to Step 10

5
  1. Disconnect the headlamp switch connector.
  2. Reconnect the LCM connectors C1 and C2.
  3. Connect a fused jumper from the headlamp switch connector cavity D (WHT) to ground.

Do the low beam headlamps light?

--

Go to Step 11

Go to Step 6

6
  1. Disconnect the LCM connector C1.
  2. Connect a fused jumper from the LCM connector C1 terminals G (RED) to F (TAN).

Do the low beam headlamps light?

--

Go to Step 13

Go to Step 7

7

Repair the open in CKT 12 (TAN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

8

Repair the open in CKT 1242 (RED) between the underhood fuse block and the LCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

9

Repair the open in CKT 351 (BLK/WHT) between S213 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 350 (BLK) between S210 and the LCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

11

Test CKT 351 (BLK/WHT) between S213 and the headlamp switch for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 351 OK?

--

Go to Step 12

Go to Step 15

12

Replace the headlamp switch.

Is the repair complete?

--

Go to Headlight System Check

--

13

Test CKT 103 (WHT) for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 103 OK?

--

Go to Step 14

Go to Step 15

14

Replace the LCM. Refer to Lamp Control Module Replacement .

Is the repair complete?

--

Go to Headlight System Check

--

15

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

Is the repair complete?

--

Go to Headlight System Check

--