GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Check the LH high beam headlamp bulbs for damage or open filament.
  2. Check the LH headlamp connector to be sure the connector seals are not damaged or missing.

Are the headlamp bulbs and connectors OK?

--

Go to Step 2

Go to Step 10

2

  1. Disconnect C141.
  2. Using a J35616-A kit connect jumpers wires between C141 terminal F female and terminal F male and terminal G female to terminal G male.
  3. Turn on the headlamps high beams on.
  4. Using a test light, probe between C141 terminal F and ground.

Does the test light illuminate?

--

Go to Step 5

Go to Step 3

3

Using a test light probe between the underhood accessory wiring junction block harness connector C3 terminal E1 and ground.

Does the test light illuminate?

--

Go to Step 4

Go to Step 9

4

Repair a poor connection or open in circuit 1640 between the underhood accessory wiring junction block harness connector C3 terminal E1 and the LH headlamp harness connector C141 terminal F.

Has the repair been made?

--

Go to Headlight System Check

--

5

  1. Disconnect C141.
  2. Using a J35616-A kit connect jumpers wires between C141 terminal F female and terminal F male and terminal G female to terminal G male.
  3. Turn the headlamps high beams on.
  4. Using a test light, probe between C141 terminal G and ground.

Does the test light illuminate?

--

Go to Step 6

Go to Step 8

6

  1. Reconnect C141.
  2. Turn the high beam headlamp on.
  3. Using a test light backprobe between the underhood accessory wiring junction block harness connector C3 terminal D8 and ground.

Does the test light illuminate?

--

Go to Step 9

Go to Step 7

7

Repair poor connection or open in circuit 1200 between the LH headlamp harness connector C141 terminal G and the underhood accessory wiring junction block harness connector C3 terminal D8.

Has the repair been made?

--

Go to Diagnostic System Check - Lighting Systems

--

8

Replace the LH headlamp. Refer to Headlamp Replacement .

Has the repair been made?

--

Go to Diagnostic System Check - Lighting Systems

--

9

Check for poor connection at the underhood accessory wiring junction block.

Is there a poor connection?

--

Go to Step 10

Go to Step 11

10

Replace the damage component or repair the poor connetion.

Has the repair been made?

--

Go to Diagnostic System Check - Lighting Systems

--

11

Replace the underhood accessory wiring junction block. Refer to Accessory Wiring Junction Block Replacement

Has the repair been made?

--

Go to Diagnostic System Check - Lighting Systems

--