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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2005 🢒 STS 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Daytime Running Lamps (DRL) Inoperative

Daytime Running Lamps (DRL) Inoperative Domestic/Canadian

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Lighting Systems Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Do the turn signals operate properly?

Go to Step 3

Go to Turn Signal Lamps and/or Indicators Inoperative

3
  1. Verify that the park brake is not APPLIED.
  2. Install a scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Parking Brake Switch parameter in the instrument panel module (IPM) inputs list.

Does the scan tool display RELEASED?

Go to Step 4

Go to Symptoms - Hydraulic Brakes

4
  1. Verify that the automatic wiper system is OFF.
  2. Install a scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Lights On With Wipers parameter in the instrument panel module (IPM) inputs list.

Does the scan tool display OFF?

Go to Step 5

Go to Symptoms - Wiper/Washer Systems

5

Inspect for poor connections at the harness connector of the IPM. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 7

Go to Step 6

6

Replace the IPM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 7

--

7

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Daytime Running Lamps (DRL) Inoperative Norway/Sweden

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Lighting Systems Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Do the low beam headlamps operate properly?

Go to Step 3

Go to Headlamps Inoperative - Low Beams

3
  1. Verify that the park brake is not APPLIED.
  2. Install a scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Parking Brake Switch parameter in the instrument panel module (IPM) inputs list.

Does the scan tool display RELEASED?

Go to Step 4

Go to Symptoms - Hydraulic Brakes

4
  1. Turn OFF the ignition.
  2. Remove the headlamp low beam relay located in the underhood fuse block.
  3. Install a test lamp between the headlamp low beam relay battery voltage circuit terminal and the headlamp low beam relay control circuit terminal. Refer to Circuit Testing .
  4. Turn ON the ignition, with the engine OFF.
  5. Operate the DRL system.

Does the test lamp illuminate?

Go to Step 6

Go to Step 5

5

Inspect for poor connections at the harness connector of the IPM. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 8

Go to Step 7

6

Replace the headlamp low beam relay. Refer to Relay Replacement .

Did you complete the replacement?

Go to Step 8

--

7

Replace the IPM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 8

--

8

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2