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Makes 🢒 GMC_Truck 🢒 2006 🢒 Canyon Pickup - 4WD 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Daytime Running Lamps (DRL) Inoperative

Daytime Running Lamps (DRL) Inoperative Early Production to VIN 68179242

Step

Action

Yes

No

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

Connector End View Reference: Lighting Systems Connector End Views , Computer/Integrating Systems Connector End Views in Computer/Integrating Systems, or Hydraulic Brake Connector End Views in Hydraulic Brakes

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Verify that the daytime running lamps (DRL) are inoperative.

Do the DRL operate normally?

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

Go to Step 3

3
  1. Block the drive wheels.
  2. Place the gear selector into the DRIVE position.
  3. Ensure that the park brake is Released.
  4. Ensure that the headlamp switch is in the AUTO position.
  5. Install a scan tool.
  6. Turn ON the ignition, with the engine OFF.
  7. With the scan tool, observe the Park Brake Switch parameter in the body control module (BCM) data list.

Does the scan tool display Released?

Go to Step 5

Go to Step 4

4

Test the signal circuit of the park brake switch for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

Go to Step 16

Go to Step 8

5

With a scan tool, observe the Headlamp Off Switch data parameter in the BCM data list.

Does the scan tool display Inactive?

Go to Step 6

Go to Step 7

6
  1. Carefully place a supplemental light source over the ambient light sensor.
  2. With the scan tool, observe the Ambient Light Sensor data parameter in the BCM data list.

Does the parameter indicate that there is sufficient light to activate the DRL?

Go to Step 11

Go to Step 9

7

Test the headlamp switch headlamps OFF signal circuit and low reference circuit of the headlamp switch for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

Go to Step 16

Go to Step 10

8

Inspect for poor connections at the harness connector of the park brake switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 12

9

Inspect for poor connections at the harness connector of the ambient light sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

10

Inspect for poor connections at the harness connector of the headlamp and panel dimmer switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 14

11

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

Did you find and correct the condition?

Go to Step 16

Go to Step 15

12

Replace the park brake switch. Refer to Parking Brake Indicator Switch Replacement in Park Brake.

Did you complete the replacement?

Go to Step 16

--

13

Replace the ambient light sensor. Refer to Ambient Light Sensor Replacement .

Did you complete the replacement?

Go to Step 16

--

14

Replace the headlamp and panel dimmer switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

Go to Step 16

--

15

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

Did you complete the replacement?

Go to Step 16

--

16
  1. Use the scan tool in order to clear any induced DTCs.
  2. Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3

Daytime Running Lamps (DRL) Inoperative Late Production after VIN 68179242

Step

Action

Yes

No

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

Connector End View Reference: Computer/Integrating Systems Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2
  1. Carefully supply sufficient light to the ambient light sensor.
  2. Place the headlamps in the AUTO position.

Do the low beam headlamp bulbs illuminate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

With a scan tool, observe the DRL Relay Command parameter in the body control module (BCM) data list.

Does the scan tool display On?

Go to Step 4

Go to Step 7

4

Test the DRL supply voltage circuit for an open, high resistance, or short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 5

5

Inspect for poor connections at the harness connector of the underhood fuse block. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 6

6

Replace the DRL relay. Refer to Relay Replacement .

Did you complete the repair?

Go to Step 9

--

7

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 8

8

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

Did you complete the replacement?

Go to Step 9

--

9

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3