Daytime Running Lamps (DRL) Inoperative. GMC Truck Yukon XL Denali 2006

GM Service Manual Online

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2006 🢒 Yukon XL Denali 🢒 Body 🢒 Lighting Systems 🢒 Daytime Running Lamps (DRL) Inoperative

Daytime Running Lamps (DRL) Inoperative Domestic

Step	Action	Yes	No
Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics Connector End View Reference: Lighting Systems Connector End Viewsor Computer/Integrating Systems Connector End Views in Computer/Integrating 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	Block the drive wheels. Turn the ignition ON, with the engine OFF. Place the gear selector in the DRIVE position. Ensure the headlamp switch is in the AUTO position. Ensure the ambient light sensor is not covered or has no obstruction to daylight. Does the system operate normally?	Go to Testing for Electrical Intermittentsin Wiring Systems	Go to Step 3
3	Is only one daytime running lamp (DRL) inoperative?	Go to Step 4	Go to Step 5
4	Test the supply and ground circuits of the affected lamp for a high resistance or an open. 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
5	Ensure the park brake is not set. Install a scan tool. Turn ON the ignition, with the engine OFF. 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 7	Go to Step 6
6	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 the condition?	Go to Step 16	Go to Step 10
7	Turn OFF the ignition. Remove the DRL relay. Connect a 3-amp fused jumper wire between battery positive voltage and the DRL supply voltage circuit of the DRL relay. Do the DRL illuminate?	Go to Step 8	Go to Step 11
8	Test the DRL relay control circuit of the DRL relay for a ground signal. Refer to Circuit Testing in Wiring Systems Is a ground signal present?	Go to Step 14	Go to Step 9
9	Inspect for poor connections at the harness connector of the BCM. 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 16	Go to Step 12
10	Inspect for poor connections at the harness connector of the park brake 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 16	Go to Step 13
11	Repair the DRL supply voltage circuit. Refer to Wiring Repairs in Wiring Systems Did you complete the repair?	Go to Step 16	--
12	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	--
13	Replace the park brake switch. Refer to Parking Brake Indicator Switch Replacement in Park Brake. Did you complete the replacement?	Go to Step 16	--
14	Replace the DRL relay. Refer to Relay Replacement in Wiring Systems. Did you complete the replacement?	Go to Step 16	--
15	Replace the inoperative DRL. Did you complete the replacement?	Go to Step 16	--
16	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 Export

Step	Action	Yes	No
Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics Connector End View Reference: Lighting Systems Connector End Viewsor Computer/Integrating Systems Connector End Views in Computer/Integrating 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	Block the drive wheels. Turn the ignition ON, with the engine OFF. Place the gear selector in the DRIVE position. Ensure the headlamp switch is in the PARK position. Does the system operate normally?	Go to Testing for Electrical Intermittentsin Wiring Systems	Go to Step 3
3	Is only one daytime running lamp (DRL) inoperative?	Go to Step 4	Go to Step 5
4	Test the supply and ground circuits of the affected lamp for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 17	Go to Step 16
5	Do the park lamps operate normally?	Go to Step 6	Go to Park, License, and Tail Lamps Inoperative
6	Ensure the park brake is not set. Install a scan tool. Turn ON the ignition, with the engine OFF. 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 8	Go to Step 7
7	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 the condition?	Go to Step 17	Go to Step 11
8	Turn OFF the ignition. Remove the DRL relay. Connect a 3-amp fused jumper wire between battery positive voltage and the DRL supply voltage circuit of the DRL relay. Do the DRL illuminate?	Go to Step 9	Go to Step 12
9	Test the DRL relay control circuit of the DRL relay for a ground signal. Refer to Circuit Testing in Wiring Systems. Is a ground signal present?	Go to Step 15	Go to Step 10
10	Inspect for poor connections at the harness connector of the BCM. 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 17	Go to Step 13
11	Inspect for poor connections at the harness connector of the park brake 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 17	Go to Step 14
12	Repair the DRL supply voltage circuit. Did you complete the repair?	Go to Step 17	--
13	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 17	--
14	Replace the park brake switch. Refer to Parking Brake Indicator Switch Replacement in Park Brake. Did you complete the replacement?	Go to Step 17	--
15	Replace the DRL relay. Refer to Relay Replacement in Wiring Systems. Did you complete the replacement?	Go to Step 17	--
16	Replace the inoperative DRL. Did you complete the replacement?	Go to Step 17	--
17	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 3