GM Service Manual Online
For 1990-2009 cars only

Headlamps Inoperative - Low Beams Eur, Jap, Chev Dom, Pont, Gulf States

Step

Action

Value(s)

Yes

No

1

Did you perform the Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the headlamps on.
  2. Turn the headlamp dimmer switch to the low beam position.

Do the low beam headlamps illuminate?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Are the low beams inoperative with the switch (Pont, Chevy Dom, Gulf States only)?

--

Go to Step 4

Go to Step 5

4

  1. Leave the headlamps on.
  2. Connect a test lamp between the headlamp switch terminal E and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 8

Go to Step 9

5

Are the low beams inoperative (DRL switch and Pontiac) only?

--

Go to Step 6

Go to Step 7

6

Repair a poor connection or an open in the signal circuit of the headlamp switch between C200D/B terminal B5 and S202. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 12

--

7

  1. Turn the headlamps on.
  2. Turn the headlamp dimmer switch to the low beam position.
  3. Connect a test lamp between the headlamp dimmer switch terminal C and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 10

Go to Step 11

8

Repair a poor connection or an open in the signal circuit of the headlamp switch. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 12

--

9

Replace the headlamp switch. Refer to Headlamp Switch Replacement or Headlamp Switch Replacement .

Did you complete the repair?

--

Go to Step 12

--

10

Repair a poor connection or an open in the supply voltage circuit of the low beam headlamps between the headlamp dimmer switch connector terminal C and S153. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 12

--

11

Replace the headlamp dimmer switch. Refer to Dimmer Switch Assembly - Disassemble - Off Vehicle and Dimmer Switch Assembly - Assemble - Off Vehicle .

Did you complete the replacement?

--

Go to Step 12

--

12

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3

Headlamps Inoperative - Low Beams Scandinavia

Step

Action

Value(s)

Yes

No

1

Did you perform the Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the headlamps on.
  2. Turn the headlamp dimmer switch to the low beam position.

Do the low beams illuminate?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Are the low beam headlamps inoperative with DRL and the switch?

--

Go to Step 4

Go to Step 5

4

Inspect the high beam headlamps.

Do they operate?

--

Go to Step 8

Go to Step 9

5

Are the low beam headlamps inoperative with just the switch?

--

Go to Step 6

Go to Step 7

6

  1. Leave the headlamps on.
  2. Leave the headlamp dimmer switch in the low beam position.
  3. Connect a test lamp between the headlamp dimmer switch terminal C and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 12

Go to Step 13

7

  1. Turn the headlamps off.
  2. Connect a test lamp between the headlamp switch terminal A and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 14

Go to Step 15

8

Repair a poor connection or an open in the supply voltage circuit of the low beam headlamps. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

--

9

Connect a test lamp between the headlamp switch terminal J and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 10

Go to Step 11

10

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

--

Go to Step 24

--

11

Repair a poor connection or an open in the battery positive voltage circuit of the headlamp switch. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

--

12

Repair a poor connection or an open in the supply voltage circuit of the low beam headlamps. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

--

13

Replace the headlamp dimmer switch. Refer to Dimmer Switch Assembly - Disassemble - Off Vehicle and Dimmer Switch Assembly - Assemble - Off Vehicle .

Did you complete the replacement?

--

Go to Step 24

--

14

Connect a test lamp between the DRL relay terminals 30 and 86. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 16

Go to Step 17

15

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

--

Go to Step 24

--

16

  1. Turn the ignition switch to the RUN position.
  2. Connect a test lamp between the DRL relay terminals 87 and 86. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 18

Go to Step 19

17

Connect a test lamp between the DRL relay terminal 30 and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 20

Go to Step 21

18

Repair a poor connection or an open in the supply voltage circuit of the low beam headlamps. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

--

19

Connect a test lamp between the DRL relay terminal 85 and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 22

Go to Step 23

20

Repair a poor connection or an open in the ground circuit of the DRL relay coil. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

--

21

Repair a poor connection or an open in the supply voltage circuit of the DRL relay switch. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

--

22

Replace the DRL relay.

Did you complete the replacement?

--

Go to Step 24

--

23

Repair a poor connection or an open in the ignition 3 voltage circuit of the DRL relay coil. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

--

24

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3