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For 1990-2009 cars only

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

Step

Action

Value(s)

Yes

No

1

Did you perform the DRL System Check?

--

Go to Step 2

Go to Daytime Running Lights (DRL) System Check

2

Use the scan tool in order to read the current body control module (BCM) diagnostic trouble codes (DTCs).

Does the scan tool show any DTCs?

--

Go to Diagnostic Trouble Code (DTC) List/Type in Body Control Systems

Go to Step 3

3

  1. Disconnect the DRL relay.
  2. Turn the ignition switch to the ON position. Do not start the engine.
  3. Connect a fused jumper wire between the DRL relay terminals 3-5.

Do the DRLs illuminate?

--

Go to Step 4

Go to Step 5

4

Replace the DRL relay.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

5

Using the J 39200 and the connector test adapter kit, test terminal 2 of the DRL relay socket in the underhood fuse block for voltage.

Is voltage present?

Battery Voltage

Go to Step 7

Go to Step 6

6

Replace the underhood fuse block.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

7

  1. Install the DRL relay.
  2. Disconnect the headlamp grounding relay.
  3. Disconnect the BCM connector C1.
  4. Turn the ignition switch to the ON position. Do not start the engine.
  5. Measure the voltage at connector C1 cavity A11.

Is voltage present?

--

Go to Step 9

Go to Step 8

8

Locate and repair the open in CKT 592.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

9

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

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

Step

Action

Value(s)

Yes

No

1

Did you perform the DRL System Check?

--

Go to Step 2

Go to Daytime Running Lights (DRL) System Check

2

  1. Turn the ignition switch to the RUN position.
  2. Connect a test lamp between ground and each test point on the back of the IGN E fuse.

Does the test lamp illuminate at both test points?

--

Go to Step 7

Go to Step 3

3

Does the test lamp illuminate at one of the test points?

--

Go to Step 4

Go to Step 14

4

  1. Remove the DRL relay.
  2. Connect a test lamp between cavity 2 and battery voltage.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 6

5

Replace the underhood fuse block.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

6

Replace the daytime running lamps (DRL) relay.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

7

Connect a test lamp between ground and each test point on the back of the DRL fuse.

Does the test lamp illuminate at both test points?

--

Go to Step 19

Go to Step 8

8

Does the test lamp illuminate at one of the test points?

--

Go to Step 10

Go to Step 9

9

Locate and repair the power feed to the DRL fuse. Refer to

Cell 10: HI BEAM, LD LEV, DRL Fuses and Low Beam Relay (Envoy Only)


Object Number: 379920  Size: FS
Power and Grounding Connector End Views
Power and Grounding Components
Cell 10: ECM B Fuse and Horn, Rear Defogger Relays
Cell 10: MIR/LKS, FOG LP Fuses and DRL, Headlamp Power Relays
Cell 10: B+ Buss Bar
in Wiring Systems.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

10

  1. Remove the DRL relay.
  2. Connect a test lamp between cavity 5 and battery voltage.

Did the test lamp illuminate?

--

Go to Step 5

Go to Step 11

11

Inspect for a short to ground in CKT 1193 (LT GRN).

Is a short present?

--

Go to Step 12

Go to Step 13

12

Repair the short to ground in CKT 1193 (LT GRN).

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

13

Replace the DRL relay.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

14

Connect a test lamp between ground and each test point on the back of the IGN A fuse.

Does the test lamp illuminate at both test points?

--

Go to Step 18

Go to Step 15

15

Does the test lamp illuminate at one of the test points?

--

Go to Step 16

Go to Step 17

16

Locate and repair a short to ground in the following circuits between the IGN A fuse and the IGN E fuse:

    • CKT 242 (RED)
    • CKT 3 (PNK)

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

17

Locate and repair the power feed to IGN A fuse. Refer to

Cell 10: Ign RUN And START Buss Bar


Object Number: 379910  Size: FS
Power and Grounding Connector End Views
Power and Grounding Components
Cell 10: Ign ACC, RUN and RAP Buss Bar
Cell 10: B+ Buss Bar
Cell 10: B+ Buss Bar
in Wiring Systems.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

18

Locate and repair an open in the following circuits between the IGN A fuse and the IGN E fuse:

    • CKT 242 (RED)
    • CKT 3 (PNK)

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

19

  1. Remove the DRL relay.
  2. Connect a fused jumper between cavity 4 and cavity 3 of the DRL relay socket.

Do the daytime running lamps illuminate?

--

Go to Step 37

Go to Step 20

20

Connect a test lamp between ground and each test point on the back of the RT HI fuse.

Does the test lamp illuminate at both test points?

--

Go to Step 28

Go to Step 21

21

Does the test lamp illuminate at one of the test points?

--

Go to Step 22

Go to Step 23

22

  1. Replace the RT HI fuse.
  2. Inspect CKT 311 (LT GRN/BLK) for an intermittent short to ground. Repair as necessary

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

23

Inspect the right high beam bulb.

Is the bulb open?

--

Go to Step 24

Go to Step 25

24

Replace the right high beam bulb.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

25

Connect a J 39200 DMM between cavity 3 at the DRL relay socket and CKT 1193 (LT GRN), cavity B at the RH high beam bulb connector.

Is the resistance less than the specified value?

0.5 ohms

Go to Step 27

Go to Step 26

26

Locate and repair an open in CKT 1193 (LT GRN) between the DRL relay and the right high beam bulb.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

27

Locate and repair an open in CKT 311 (LT GRN/BLK) between the following components:

    • The right high beam bulb
    • The RT HI fuse

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

28

Connect a test lamp between ground and each test point on the back of the LT HI fuse.

Does the test lamp illuminate at both of the test points?

--

Go to Step 32

Go to Step 29

29

Does the test lamp illuminate at one of the test points?

--

Go to Step 31

Go to Step 30

30

Replace the underhood fuse block.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

31

Locate and repair a short to ground in CKT 711 (DK GRN/WHT).

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

32

Inspect the left high beam bulb.

Is the bulb open?

--

Go to Step 33

Go to Step 34

33

Replace the left high beam bulb.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

34

Connect a test lamp between CKT 711 (DK GRN/WHT) and ground.

Does the test lamp illuminate?

--

Go to Step 36

Go to Step 35

35

Locate and repair an open in CKT 711 (DK GRN/WHT).

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

36

Locate and repair an open in CKT 150 (BLK).

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

37

  1. Connect a scan tool to the vehicle.
  2. Inspect the system. Refer to Diagnostic System Check - Body Control System in Body Control System. Return here if the system check reports SYSTEM NORMAL.
  3. Select Body Control Module.
  4. Read the Daytime Running Lamps status.

Does the Daytime Running Lamps status display the specified value?

ACTIVE

Go to Step 44

Go to Step 38

38

  1. Select Body Control Module.
  2. Read the Park Brake Switch status.

Does the Park Brake Switch status display the specified value?

SET

Go to Step 39

Go to Step 43

39

  1. Inspect the parking brake in order to ensure that the parking brake is not set.
  2. Disconnect the parking brake switch connector.
  3. Select Body Control Module.
  4. Read the Park Brake Switch status.

Does the Park Brake Switch status display the specified value?

SET

Go to Step 40

Go to Step 42

40

Inspect for a short to ground in CKT 80 (LT GRN) between the parking brake switch and BCM connector C1.

Is circuit OK?

--

Go to Step 43

Go to Step 41

41

Repair the short to ground in CKT 80 (LT GRN) between the parking brake switch and BCM connector C1.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

42

Adjust or replace the parking brake switch as necessary.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

43

Replace the body control module. Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

44

  1. Reinstall the DRL relay.
  2. Use a fused jumper in order to backprobe between CKT 592 (LT GRN/BLK), cavity A11 connector C1 at the BCM and ground.

Do the daytime running lamps illuminate?

--

Go to Step 43

Go to Step 45

45

  1. Remove the DRL relay.
  2. Using the J 35616-A , connect a test lamp between cavity 2 and cavity 1 at the DRL relay socket.
  3. Turn the ignition switch to the RUN position.
  4. Verify active DRL status.

Does the test lamp illuminate?

--

Go to Step 46

Go to Step 47

46

Replace the DRL relay.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

47

Locate and repair the open in CKT 592 (LT GRN/BLK) between the DRL relay cavity 2 and the BCM.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--