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For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1999 🢒 Aurora 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Headlamps Inoperative - Low Beams

Headlamps Inoperative - Low 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 lamp control module (LCM) connector C2.
  2. Connect a DMM from the LCM connector C2 cavity G (ORN) to ground.

Is the voltage within the specified range?

10-15V

Go to Step 3

Go to Step 9

3

Connect a DMM from the LCM connector C2 cavity G (ORN) to cavity E (BLK).

Is the voltage within the specified range?

10-15V

Go to Step 4

Go to Step 10

4
  1. Disconnect the LCM connector C1.
  2. Connect a DMM from the LCM connector C2 cavity G (ORN) to the LCM connector C1 cavity B4 (BLK/WHT).

Is the voltage within the specified range?

10-15V

Go to Step 5

Go to Step 11

5

Connect a DMM from the LCM connector C2 cavity G (ORN) to the LCM connector C1 cavity B5 (BLK/WHT)

Is the voltage within the specified range?

10-15V

Go to Step 6

Go to Step 11

6
  1. Reconnect the LCM connectors C1 and C2.
  2. Disconnect the headlamp switch connector.
  3. Connect a fused jumper from the headlamp switch connector cavity 6 (WHT) to ground.

Do the low beam headlights turn on?

--

Go to Step 12

Go to Step 7

7
  1. Disconnect the LCM connector C2.
  2. Connect a fused jumper between the LCM connector C2 cavity G (ORN) and cavity F (TAN).

Do the low beam headlights turn on?

--

Go to Step 14

Go to Step 8

8

Repair the open in CKT 12 (TAN) between the LCM and S120. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

9

Repair the open in CKT 1740 (ORN) between the RH rear fuse block 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 150 (BLK) between S290 and the LCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

11

Repair the open in CKT 351 (BLK/WHT) between S263 and the LCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

12

Inspect for an open in CKT 150 (BLK) between S273 and the headlamp switch. Refer to Testing for Continuity in Wiring Systems.

Is CKT 150 OK?

--

Go to Step 13

Go to Step 16

13

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Is the repair complete?

--

Go to Headlight System Check

--

14

Inspect for an open in CKT 103 (WHT) between the LCM and the headlamp switch. Refer to Testing for Continuity in Wiring Systems.

Is CKT 103 OK?

--

Go to Step 15

Go to Step 16

15

Replace the lamp control module (LCM).

Is the repair complete?

--

Go to Headlight System Check

--

16

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

Is the repair complete?

--

Go to Headlight System Check

--

Headlamps Inoperative - Low 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 C2.
  2. Connect a DMM from the LCM connector C2 cavity E (ORN) to ground.

Is the voltage within the specified range?

10-15V

Go to Step 3

Go to Step 11

3
  1. Disconnect the LCM connector C1.
  2. Connect a DMM from the LCM connector C2 cavity E (ORN) to the LCM connector C1 cavity A5 (BLK/WHT).

Is the voltage within the specified range?

10-15V

Go to Step 4

Go to Step 12

4

Connect a DMM from the LCM connector C2 cavity E (ORN) to the LCM connector C1 cavity B6 (BLK/WHT).

Is the voltage within the specified range?

10-15V

Go to Step 5

Go to Step 12

5
  1. Place the headlamp switch in the ON position.
  2. Connect a DMM from the LCM connector C2 cavity E (ORN) to connector C1 cavity B1 (WHT).

Is the voltage within the specified range?

10-15V

Go to Step 6

Go to Step 13

6

Connect a fused jumper from the LCM connector C2 cavity E (ORN) to cavity D (LT BLU).

Do the low beam headlights turn on?

--

Go to Step 18

Go to Step 7

7
  1. Disconnect the headlamp dimmer switch connector C202.
  2. Connect a fused jumper across the LCM connector C2 cavity E (ORN) to the headlamp dimmer switch connector C202 cavity E12 (TAN).

Do the low beam headlights turn on?

--

Go to Step 9

Go to Step 8

8

Repair the open in CKT 12 (TAN) between the headlamp dimmer switch connector C202 and S120. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

9

Inspect for an open in CKT 1346 (LT BLU) between the LCM and the headlamp dimmer switch connector C202. Refer to Testing for Continuity in Wiring Systems.

Is CKT 1346 OK?

--

Go to Step 10

Go to Step 19

10

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

--

11

Repair the open in CKT 1740 (ORN) between the RH rear fuse block and the LCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

12

Repair the open in CKT 351 (BLK/WHT) between S263 and the LCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

13

Backprobe the LCM connector C2 with a DMM from cavity E (ORN) to the headlamp dimmer switch connector C202 cavity E9 (WHT).

Is the voltage within the specified range?

10-15V

Go to Step 17

Go to Step 14

14

Backprobe the LCM connector C2 with a DMM from cavity E (ORN) to the headlamp switch connector C202 cavity E6 (BLK/WHT).

Is the voltage within the specified range?

10-15V

Go to Step 16

Go to Step 15

15

Repair the open in CKT 351 (BLK/WHT) between the headlamp switch connector C202 and S263. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

16

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Is the repair complete?

--

Go to Headlight System Check

--

17

Repair the open in CKT 103 (WHT) between the LCM and the headlamp switch connector C202. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

18

Replace the lamp control module (LCM).

Is the repair complete?

--

Go to Headlight System Check

--

19

Repair the open in CKT 1346 (LT BLU) between the LCM and the headlamp dimmer switch connector C202. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--