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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2000 🢒 Savana 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Headlamps Inoperative - Low Beams

Headlamps Inoperative - Low Beams Domestic

Step

Action

Value(s)

Yes

No

DEFINITION: The low beam headlamps do not operate on either side of the vehicle, but there is no problem with the high beam headlamps.

1

Review the headlamp operation and perform the necessary inspections.

Did you complete the system review and inspection?

--

Go to Step 2

Go to Symptoms

2

Attempt to operate the headlamps.

Do the low beam headlamps operate normally?

--

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

Go to Step 3

3
  1. Turn on the low beam headlamps.
  2. Test the voltage of CKT 359 (PPL) at connector C200 terminal E12. The voltage can be tested without disconnecting the connector.

Did the test indicate battery voltage?

B+

Go to Step 5

Go to Step 4

4

Replace the multifunction switch. Refer to Multifunction, Turn Signal and Hazard Switch Replacement - On Vehicle .

Did you complete the repair?

--

Go to Step 10

--

5
  1. Remove the DRL relay from the instrument panel (IP) relay center.
  2. Connect a 40A fused jumper wire from C2 to D3 of the relay socket.
  3. Turn on the low beam headlamps.

Did the low beam headlamps illuminate?

--

Go to Step 6

Go to Step 7

6

Replace the DRL relay.

Did you complete the repair?

--

Go to Step 10

--

7
  1. Remove the jumper wire.
  2. With the DRL relay removed, turn on the low beam headlamps.
  3. Test for voltage at cavity C2 in the DRL relay socket.

Is battery voltage available at cavity C2 in the DRL relay socket?

B+

Go to Step 9

Go to Step 8

8

Repair the open CKT 359 (PPL).

Did you complete the repair?

--

Go to Step 10

--

9

Repair the open CKT 12 (TAN) between the DRL relay and splice S143.

Did you complete the repair?

--

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3

Headlamps Inoperative - Low Beams Export

Step

Action

Value(s)

Yes

No

DEFINITION: The low beam headlamps do not operate on either side of the vehicle, but there is no problem with the high beam headlamps. This applies only to systems which are also equipped with daytime running lamps.

1

Review the headlamps operation and perform the necessary inspections.

Did you complete the system review and inspection?

--

Go to Step 2

Go to Symptoms

2

Attempt to operate the headlamps.

Do the low beam headlamps operate normally?

--

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

Go to Step 3

3
  1. Turn on the low beam headlamps.
  2. Test for voltage by backprobing CKT 359 (PPL) at connector C200 cavity E12.

Did backprobing indicate battery voltage?

B+

Go to Step 5

Go to Step 4

4

Replace the multifunction switch. Refer to Multifunction, Turn Signal and Hazard Switch Replacement - On Vehicle .

Did you complete the repair?

--

Go to Step 10

--

5
  1. Remove the DRL relay from the instrument panel (IP) relay center.
  2. Connect a 40A fused jumper wire from cavity C2 to D3 in the DRL relay socket.
  3. Turn on the low beam headlamps.

Did the low beam headlamps illuminate?

--

Go to Step 6

Go to Step 7

6

Replace the DRL relay.

Did you complete the repair?

--

Go to Step 10

--

7
  1. With the DRL relay removed, turn on the low beam headlamps.
  2. Test for voltage at cavity C2 in the DRL relay socket.

Is battery voltage available at cavity C2 in the DRL relay socket?

B+

Go to Step 8

Go to Step 9

8

Repair the open CKT 359 (PPL) between connector C200 and the DRL relay.

Did you complete the repair?

--

Go to Step 10

--

9

Repair the open CKT 12 (TAN) between the DRL relay and the HDLP fuses in the underhood fuse-relay center.

Did you complete the repair?

--

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3