Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems.

1

Was the Lighting System Diagnostic System Check performed?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

Important:: Vehicle shift lever must be out of the PARK position in order for the daytime running lamps (DRL) to operate.

1. Turn ON the ignition, with the engine OFF.
2. Place the headlight switch to the AUTO position.
3. Depress and hold the brake pedal.
4. Move the gear selector out of park position.
5. Verify the parking brake is disengaged.
6. Expose the ambient light sensor to a bright incandescent light.
7. Wait more than 20 seconds.
8. Observe the DRL lamps.
9. Place the gear selector in the park position.
10. Release the brake pedal.

Did the DRL operate properly?

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

Go to Step 3

Do the turn signal lamps operate properly?

Go to Step 4

Go to Turn Signal Lamps and/or Indicators Inoperative

Is the DRL always in the daylight mode (turn signal lamps ON at all time)?

Go to Step 12

Go to Step 5

1. Disconnect the DRL ambient light sensor.
2. At the DRL ambient light sensor harness connector, attach a 3 Amp fused jumper between the DRL ambient light sensor signal circuit and the DRL ambient light sensor reference signal circuit.

Are the turn signal lamps on at all times?

Go to Step 18

Go to Step 6

1. Disconnect the DRL control module.
2. Turn the ignition to the RUN position with the engine off.
3. Using a test lamp connected to ground, probe the DRL control module harness connector ignition 3 voltage circuit.

Does the test lamp illuminate?

Go to Step 7

Go to Step 20

Using a test lamp connected to a good ground, probe the DRL control module harness connector ignition 1 voltage circuit.

Does the test lamp illuminate?

Go to Step 8

Go to Step 21

Using a test lamp connected to a good ground, probe the DRL control module harness connector park lamp fused battery positive voltage circuit.

Does the test lamp illuminate?

Go to Step 9

Go to Step 22

1. Using a test lamp connected to ground probe the DRL control module harness connector headlamp supply voltage circuit.
2. Turn the headlamp switch to the HEAD position.

Does the test lamp illuminate?

Go to Step 10

Go to Step 23

Using a test lamp, probe the DRL control module between the battery positive voltage circuit and the DRL ground circuit.

Does the test lamp illuminate?

Go to Step 11

Go to Step 24

Using a test lamp, probe the DRL control module harness connector between the headlamp circuit breaker battery positive voltage supply circuit and the DRL low beam supply voltage ground circuit.

Does the test lamp illuminate?

Go to Step 17

Go to Step 19

Disconnect the DRL ambient light sensor.

Does the DRL change modes?

Go to Step 18

Go to Step 13

Test for a short to ground in the DRL ambient light sensor signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 14

Test for a short to ground in the ambient light sensor low reference circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 15

Test for a high resistance or an open in the DRL ambient light sensor signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 16

Test for a high resistance or an open in the DRL ambient light sensor low reference circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 17

Inspect for a poor connection at the harness connector of the DRL control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 25

Inspect for a poor connection at the harness connector of the ambient light sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 26

Repair a open or high resistance in the Circuit Breaker headlamp supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

--

Repair a open, high resistance or short to ground in the ignition 3 voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 27

--

Repair a open, high resistance or short to ground in the ignition 1 voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 27

--

Repair a open, high resistance or short to ground in the park lamp fused battery positive voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 27

--

Repair a open or high resistance in the headlamp switch supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 27

--

Repair a open or high resistance in the ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 27

--

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

Did you complete the replacement?

Go to Step 27

--

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

Did you complete the replacement?

Go to Step 27

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems.

1

Was the Lighting System Diagnostic System Check performed?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

Important:: Vehicle shift lever must be out of the PARK position in order for the daytime running lamps (DRL) to operate.

1. Turn ON the ignition, with the engine OFF.
2. Place the headlight switch to the AUTO position.
3. Depress and hold the brake pedal.
4. Move the gear selector out of park position.
5. Verify the parking brake is disengaged.
6. Expose the ambient light sensor to a bright incandescent light.
7. Wait more than 20 seconds.
8. Observe the DRL lamps.
9. Place the gear selector in the park position.
10. Release the brake pedal.

Did the DRL operate properly?

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

Go to Step 3

Is the LOW OIL Pressure indicator ON?

Go to Engine Oil Pressure Indicator Always On in Instrument Panel, Gages and Console

Go to Step 4

Are both the low beam headlamps and rear tail lamps inoperative?

Go to Step 7

Go to Step 5

Are the low beam headlamps inoperative?

Go to Step 6

Go to Step 12

1. Place the headlamp switch in the HEAD position.
2. Place the headlamp dimmer switch in the low beam position.

Do the low beam headlamps illuminate?

Go to Step 9

Go to Headlamps Inoperative - Low Beams

1. Place the ignition switch in the OFF position.
2. Disconnect the Daytime Running Lamp (DRL) control module connector.
3. Place the ignition switch in the ON position.
4. Using a test lamp connected to ground, probe the ignition 3 voltage circuit of the DRL control module connector.

Does the test lamp illuminate?

Go to Step 8

Go to Step 16

Using a test lamp connected to battery positive voltage, probe the ground circuit of the daytime running lamp (DRL) control module.

Does the test lamp illuminate?

Go to Step 18

Go to Step 19

1. Place the headlamp switch in the OFF position.
2. Place the ignition switch in the OFF position.
3. Disconnect the daytime runninglLamp (DRL) control module connector.
4. Probe the headlamps OFF input circuit of the Daytime Running Lamp (DRL) control module with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 10

Go to Step 15

With a test lamp that is connected to ground, probe the battery positive voltage circuit of the daytime running lamp (DRL) control module connector that is fed by the HEAD LAMP circuit breaker.

Does the test lamp illuminate?

Go to Step 11

Go to Step 20

Connect a fused jumper between battery positive voltage and the low beam supply voltage circuit of the daytime running lamp (DRL) control module. Refer to Circuit Testing in Wiring Systems.

Do the low beam headlamps illuminate?

Go to Step 18

Go to Step 21

Place the headlamp switch in the PARK position.

Do the tail lamps illuminate?

Go to Step 13

Go to Park Lamps Inoperative

1. Place the ignition switch in the OFF position.
2. Disconnect the daytime runninglLamp (DRL) control module connector.
3. Place the ignition switch in the ON position.
4. Place the headlamp switch in the OFF position.
5. Using a test lamp connected to ground, probe the battery positive circuit of the daytime running lamp (DRL) control module that is fed by the PARK LP fuse.

Does the test lamp illuminate?

Go to Step 14

Go to Step 22

Connect a fused jumper between battery positive voltage and the park lamps supply voltage circuit of the DRL control module . Refer to Circuit Testing in Wiring Systems.

Do the tail lamps illuminate?

Go to Step 18

Go to Step 23

Test for a open or high resistance in the headlamps OFF input circuit of the DRL control module . Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 17

Test for a open or high resistance in the ignition 3 voltage circuit of the DRL control module . Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 24

Inspect for poor connections at the harness connector of the headlamp switch . Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 26

Inspect for poor connections at the harness connector of the daytime running lamps control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 27

Go to Step 25

Repair an open or high resistance in the ground circuit of the DRL control module . Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 27

--

Repair an open or high resistance in the battery positive voltage circuit of the DRL control module connector that is fed by the HEAD LAMP circuit breaker. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 27

--

Repair an open or high resistance in the headlamp low beam supply voltage circuit of the DRL control module connector. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 27

--

Repair an open or high resistance in the battery positive circuit of the DRL control module that is fed by the PARK LP fuse. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 27

--

Repair an open or high resistance in the park lamps supply voltage circuit of the DRL control module. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 27

--

Repair a short to ground in the ignition 3 voltage circuit in the DRL control module . Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 27

--

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

Is the repair complete?

Go to Step 27

--

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Is the repair complete?

Go to Step 27

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2