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

Headlamps Inoperative - Low Beams Domestic

Step

Action

Value(s)

Yes

No

1

Was the Headlight System Check performed?

--

Go to Step 2

Go to Headlight System Check

2
  1. Connect a J 39200 DMM between connector C200, cavity E13 for CKT 6 (LT BLU) and cavity E12 for CKT 12 (TAN).
  2. Operate the headlamp dimmer switch at least twice.
  3. Select the low beam.

Is continuity present?

--

Go to Step 5

Go to Step 3

3
  1. Locate an open in CKT 12 (TAN) in the steering column.
  2. Repair the open, as necessary.

Did you repair an open?

--

Go to Headlight System Check

Go to Step 4

4

Replace the headlamp dimmer switch.

Are the low beam headlamps operative?

--

Go to Headlight System Check

Go to Step 5

5
  1. Reconnect connector C200.
  2. Remove the daytime running lamp (DRL) relay from the instrument panel (IP) relay center.
  3. Connect an unpowered test lamp between the IP relay center, cavity C2, and ground.
  4. Place the headlamp switch in the headlamp position.
  5. Place the headlamp dimmer switch in the LO position.

Does the test lamp light?

--

Go to Step 6

Go to Step 7

6

Replace the DRL relay.

Are the low beam headlamps operative?

--

Go to Headlight System Check

Go to Step 7

7

Repair the open in CKT 359 (PPL) between the IP relay center, cavity C2, and connector C200, cavity E12.

Are the low beam headlamps operative?

--

Go to Headlight System Check

--

Headlamps Inoperative - Low Beams Export

Step

Action

Value(s)

Yes

No

1

Was the Headlight System Check performed?

--

Go to Step 2

Go to Headlight System Check

2
  1. Disconnect C200 at the steering column.
  2. Connect a J 39200 DMM between connector C200 cavity E13 for CKT 10 (LT BLU) pigtail wire.
  3. Connect a J 39200 DMM between connector C200 cavity E12 for CKT 12 (TAN) pigtail wire.
  4. Operate the headlamp dimmer switch at least twice. Select the low beam.

Is continuity present?

--

Go to Step 4

Go to Step 3

3

Locate and repair the open in CKT 12 (TAN) pigtail wire in the steering column. If the wire is not open, replace the headlamp dimmer switch.

Is the repair complete?

--

Go to Headlight System Check

--

4
  1. Disconnect C100.
  2. Connect a J 39200 DMM between the following components for CKT 12 (TAN):
    3. • Connector C200 cavity E12
    • Connector C100 cavity B1

Is continuity present?

--

Go to Step 5

Go to Step 6

5

Locate and repair the open in CKT 12 (TAN) between C100 and the underhood fuse-relay center.

Is the repair complete?

--

Go to Headlight System Check

--

6

Locate and repair the open in CKT 12 (TAN) between the following components:

    • Connector C200 cavity E12
    • Connector C100 cavity B1

Is the repair complete?

--

Go to Headlight System Check

--