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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2000 🢒 Savana 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Daytime Running Lamps (DRL) Inoperative, Headlamp Switch Operates Normally

Daytime Running Lamps (DRL) Inoperative, Headlamp Switch Operates Normally Domestic

Step

Action

Value(s)

Yes

No

1

Review the daytime running lamp (DRL) 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 DRL.

Does the system operate normally?

--

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

Go to Step 3

3
  1. Turn the ignition ON with the engine OFF.
  2. Release the park brake.
  3. Observe the DRL indicator in the IP cluster.

Does the DRL indicator turn on?

--

Go to Step 11

Go to Step 4

4
  1. Inspect the DRL connector and DRL control module for any damaged pins or terminals.
  2. If you observed any damaged pins or terminals, repair them.

Did you repair any damaged pins or terminals?

--

Go to Step 15

Go to Step 5

5
  1. Turn the ignition ON with the engine off.
  2. Measure the voltage at cavity C of the DRL control module connector.
  3. If you measured less than battery voltage, repair the open CKT 39 (PNK) between the GAUGES fuse and the DRL control module.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 6

6
  1. Test for an open CKT 150 (BLK) between the DRL control module connector cavity H and ground.
  2. If an open circuit was located, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 7

7
  1. Release the park brake.
  2. Disconnect the connector from the DRL control module.
  3. At cavity A of the connector, test for continuity with ground.
  4. At cavity B of the connector, test for continuity with ground.

Does either test indicate continuity with ground?

--

Go to Step 8

Go to Step 9

8

Repair the short to ground in CKT 1134 (LT BLU).

Did you complete the repair?

--

Go to Step 15

--

9
  1. Turn the ignition switch ON with the engine OFF.
  2. At the DRL control module connector cavity D, test the headlamp input circuit CKT 10 (YEL) for a short to voltage.
  3. If a short to voltage was located, repair it.

Did you locate and repair a short to voltage on the headlamp input circuit to the DRL control module?

--

Go to Step 15

Go to Step 10

10

Replace the DRL control module.

Did you complete the repair?

--

Go to Step 15

--

11
  1. Test for an open circuit CKT 340 (ORN) between the DRL fuse and the DRL relay.
  2. If you located an open circuit, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 12

12
  1. Test for an open circuit CKT 39 (PNK) between the GAUGES fuse and the DRL relay.
  2. If you located an open circuit, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 13

13
  1. Test for an open circuit CKT 592 (LT GRN/BLK) between the DRL relay socket cavity D1 and the DRL control module connector cavity G.
  2. If you located an open circuit, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 14

14

Replace the daytime running lamp relay.

Is the repair complete?

--

Go to Step 15

--

15

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3

Daytime Running Lamps (DRL) Inoperative, Headlamp Switch Operates Normally Export

Step

Action

Value(s)

Yes

No

1

Review the daytime running lamp (DRL) 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 DRL.

Does the system operate normally?

--

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

Go to Step 3

3
  1. Remove the DRL relay.
  2. Turn the ignition ON with the engine OFF.
  3. Release the park brake.
  4. Connect one lead of a digital voltmeter to B+ and with the other lead probe the DRL relay socket at cavity D1.

Does the meter indicate battery voltage?

B+

Go to Step 10

Go to Step 4

4
  1. Test for an open circuit (CKT 592 LT GRN/BLK) between the DRL relay socket cavity D1 and the DRL control module connector cavity G.
  2. If you located an open circuit, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 5

5
  1. Inspect the DRL connector and DRL control module for any damaged pins or terminals.
  2. If you observed any damaged pins or terminals, repair them.

Did you repair any damaged pins or terminals?

--

Go to Step 15

Go to Step 6

6
  1. Test for an open module power supply circuit (CKT 39 PNK) between the GAUGES fuse and the DRL control module connector cavity C.
  2. If an open circuit was located, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 7

7
  1. Test for an open ground circuit (CKT 150 BLK) between the DRL control module connector cavity  H and ground.
  2. If an open circuit was located, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 8

8

At DRL control module connector cavities A and B, test CKT 1134 LT BLU for a short to ground.

Did CKT 1134 LT BLU display a short to ground?

--

Go to Step 8

Go to Step 9

9

Repair the short to ground in CKT 1134 (LT BLU).

Did you complete the repair?

--

Go to Step 15

--

10
  1. Turn the ignition switch ON with the engine OFF.
  2. Test the parklamp input circuit (CKT 9 BRN) at the DRL control module connector cavity D for a short to voltage.
  3. If a short to voltage was located, repair it.

Did you locate and repair a short to voltage on the parklamp input circuit (CKT 9 BRN)?

--

Go to Step 15

Go to Step 11

11

Replace the DRL control module.

Did you complete the repair?

--

Go to Step 15

--

12
  1. Test for an open circuit (CKT 340 ORN) between the DRL fuse and the DRL relay.
  2. If you located an open circuit, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 13

13
  1. Test for an open circuit (CKT 39 PNK) between the GAUGES fuse and the DRL relay.
  2. If you located an open circuit, repair it.

Did you locate and repair an open circuit?

--

Go to Step 15

Go to Step 14

14

Replace the daytime running lamp relay.

Is the repair complete?

--

Go to Step 15

--

15

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3