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For 1990-2009 cars only

Daytime Running Lamps (DRL) Headlamps Inoperative Domestic

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Test the operation of the Daytime Running Lights.

Do the Daytime Running Lights operate normally?

--

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

Go to Step 3

3

Inspect the DRL fuse and the HVAC/DRL fuse.

Is either fuse open?

--

Go to Step 4

Go to Step 5

4

Repair a short to ground the respective ignition voltage circuit. Refer to Wiring Repairs

Is the repair complete?

--

Go to Step 20

--

5

  1. Turn the ignition to the RUN position.
  2. Release the park brake.
  3. Apply a bright light to the DRL ambient light sensor.

Do the front turn signal lamps light?

--

Go to Step 14

Go to Step 6

6

Use a test lamp to test for voltage at both ignition voltage circuits at the Daytime Running Lamp (DRL) control module. Refer to Circuit Testing

Does the test lamp illuminate at both ignition voltage circuits?

--

Go to Step 8

Go to Step 7

7

Repair the following:

    • an open
    • poor connection

in the respective ignition voltage circuit. Refer to Wiring Repairs

Is the repair complete?

--

Go to Step 20

--

8

Use a test lamp to verify the ground circuit at the Daytime Running Lamp (DRL) control module. Refer to Circuit Testing

Does the test lamp illuminate?

--

Go to Step 10

Go to Step 9

9

Repair the following:

    • an open
    • poor connection

in the ground circuit. Refer to Wiring Repairs

Is the repair complete?

--

Go to Step 20

--

10

Use a test lamp to verify the park brake signal circuit at the Daytime Running Lamp (DRL) control module. Refer to Circuit Testing

Does the test lamp illuminate?

--

Go to Step 11

Go to Step 14

11

  1. Disconnect the Park Brake Indicator Switch
  2. Use a test lamp to verify the park brake signal circuit at the Daytime Running Lamp (DRL) control module. Refer to Circuit Testing

Does the test lamp illuminate?

--

Go to Step 12

Go to Step 13

12

  1. Repair a short to ground in the park brake signal circuit. Refer to Wiring Repairs
  2. Inspect the system.

Is the repair complete?

--

Go to Step 20

--

13

  1. Adjust or replace the parking brake indicator switch. Refer to Parking Brake Indicator Switch Replacement in Park Brake.
  2. Inspect the system.

Is the repair complete?

--

Go to Step 20

--

14

Cover the DRL ambient light sensor.

Do the low beam headlamps and the park lamps turn on, and the turn signal lamps turn off?

--

Go to Step 20

Go to Step 15

15

Disconnect the DRL ambient light sensor.

Do the low beam headlamps and park lamps turn on?

--

Go to Step 16

Go to Step 17

16

Replace the DRL ambient light sensor. Refer to Daytime Running Lamp (DRL) Ambient Light Sensor Replacement .

Is the repair complete?

--

Go to Step 20

--

17

Use a digital multimeter (DMM) in order to test for continuity in the DRL ambient light sensor signal circuit and the ambient light sensor ground circuit.

Is there continuity in both ambient light sensor circuits?

--

Go to Step 19

Go to Step 18

18

Repair the following:

    • an open
    • poor connection

in the appropriate ambient light sensor circuit. Refer to Wiring Repairs

Is the repair complete?

--

Go to Step 20

--

19

  1. Replace the DRL control module. Refer to Daytime Running Lights (DRL) Control Module Replacement
  2. Inspect the system.

Is the repair complete?

--

Go to Step 20

--

20

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2

Daytime Running Lamps (DRL) Headlamps Inoperative Export

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Place the headlamp switch in the OFF position.
  2. Turn the ignition switch to RUN.
  3. Using a test lamp, backprobe the DRL control module connector C2 terminal F to ground.

Does the test lamp light?

--

Go to Step 4

Go to Step 3

3

Repair the following conditions in CKT 241:

    • an open
    • a poor connection

Has the repair been made and the system rechecked?

--

Go to Step 15

--

4

Using a test lamp, backprobe the DRL control module connector C2 terminal F to terminal B.

Does the test lamp light?

--

Go to Step 6

Go to Step 5

5

Repair the following conditions in CKT 1450 between the DRL control module connector C2 terminal B and S230:

    • an open
    • a poor connection

Has the repair been made and the system rechecked?

--

Go to Step 15

--

6

Using a test lamp, backprobe the DRL control module connector C1 terminal D to terminal B.

Does the test lamp light?

--

Go to Step 8

Go to Step 7

7

Repair the following conditions in CKT 2340:

    • an open
    • a poor connection

Has the repair been made and the system rechecked?

--

Go to Step 15

--

8

Start the engine, allow to idle.

Is the LOW OIL Indicator ON?

--

Go to Step 9

Go to Step 10

9

Inspect for a short to ground in CKT 231.

If OK, replace the engine oil pressure indicator switch.

Has the repair been made and the system rechecked?

--

Go to Step 15

--

10

Using a test lamp, backprobe the DRL control module connector C2 terminal C to ground.

Does the test lamp light?

--

Go to Step 12

Go to Step 11

11

  1. Repair the following conditions in CKT 1872 between the headlamp switch and the DRL control module connector C1 terminal E:
  2. • an open
    • a poor connection
  3. If the CKT is OK, replace the headlamp and IP lamp dimmer switch. Refer to Headlamp Switch Replacement .

Has the repair been made and the system rechecked?

--

Go to Step 15

--

12

Using a test lamp, backprobe the DRL control module connector C1 terminal E to ground.

Does the test lamp light?

--

Go to Step 14

Go to Step 13

13

Replace the DRL control module. Refer to Daytime Running Lights (DRL) Control Module Replacement

Has the repair been made and the system rechecked?

--

Go to Step 15

--

14

Repair the following conditions in CKT 12 between S261 and the DRL control module connector C1 terminal E:

    • an open
    • a poor connection

Has the repair been made and the system rechecked?

--

Go to Step 15

--

15

  1. Connect all connectors that were previously disconnected.
  2. Verify that the daytime running lamps operate properly.

Do the daytime running lamps operate properly?

--

System OK

Go to Step 2