GM Service Manual Online
For 1990-2009 cars only

Park Lamps Always On Domestic

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

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

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn the ignition switch to the OFF Position.
  2. Turn the headlamp switch to the OFF Position.

Are the park lamps illuminated?

Go to Step 5

Go to Step 3

3

  1. Expose the ambient light sensor a bright incandescent light.
  2. Turn the ignition switch to the RUN Position.

Are the park lamps illuminated?

Go to Step 4

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

4

Are the daytime running lamps (DRL) illuminated?

Go to Step 8

Go to Daytime Running Lamps (DRL) Inoperative

5

Disconnect the headlamp switch connector.

Do all the park lamps turn off?

Go to Step 9

Go to Step 6

6

Disconnect the DRL control module connectors.

Do all the lamps turn off?

Go to Step 8

Go to Step 7

7

Repair a short to battery positive voltage in the park lamps supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 10

--

8

Replace the DRL control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Is the repair complete?

Go to Step 10

--

9

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Is the repair complete?

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Park Lamps Always On Export

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

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

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn the ignition switch to the RUN position, with the engine OFF.
  2. Turn the headlamp switch to the OFF position.

Are the park lamps illuminated?

Go to Step 3

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

3

Is the vehicle equipped with daytime running lamps?

Go to Step 5

Go to Step 4

4

Disconnect the headlamp switch connector.

Do the park lamps turn OFF?

Go to Step 12

Go to Step 9

5

Are the headlamps illuminated?

Go to Headlamp Low or High Beams Always On

Go to Step 6

6

Disconnect the daytime running lamp (DRL) control module connector.

Are the park lamps illuminated?

Go to Step 10

Go to Step 7

7

  1. Insure that the headlamp switch is in the OFF position.
  2. Using a test lamp connected to ground, probe the park lamp supply voltage circuit that is an input to the daytime running lamp module connector.

Does the test lamp illuminate?

Go to Step 8

Go to Step 11

8

  1. Disconnect the headlamp switch connector.
  2. With a test lamp that is connected to ground, probe the parklamp supply voltage circuit that is an input to the daytime running lamp module connector.

Does the test lamp illuminate?

Go to Step 9

Go to Step 12

9

Repair a short to battery positive voltage in the park lamps supply voltage circuit of the headlamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 13

--

10

Repair a short to battery positive voltage in the park lamps supply voltage circuit that is an output of the daytime running lamp control module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 13

--

11

Replace the DRL control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Is the repair complete?

Go to Step 13

--

12

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Is the repair complete?

Go to Step 13

--

13

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2