For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the DRL System Check? | -- | Go to Step 2 | Go to Daytime Running Lights (DRL) System Check
2 |

1. Test the body control module (BCM) for DTCs. Refer to Body Control Module System Check in Body Control System.
2. Correct all of the current DTCs before proceeding with this diagnosis.

Are all of the code setting conditions corrected?

--

Go to Step 3

Go to Step 13

3 |

1. Connect a Scan Tool to the data link connector (DLC).
2. Use Scan Tool in order to command the headlamps on.

Do the headlamps light?

--

Go to Step 13

Go to Step 4

4 | Use a test lamp in order to backprobe the turn/headlamp switch assembly between terminal 36 of connector C1 and ground. Does the test lamp light? | -- | Go to Step 4 | Go to Step 6
5 |

1. Exchange the automatic lamp control relay with a known good relay from the underhood junction block.
2. Use Scan Tool in order to command the headlamps on.

Do the headlamps light?

--

Go to Step 7

Go to Step 8

6 | Replace the turn/headlamp switch assembly. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column-Tilt. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
7 | Replace the faulty relay. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
8 | Use a test lamp in order to backprobe the underhood junction block between terminal B3 of connector C3 and ground. Does the test lamp light? | -- | Go to Step 9 | Go to Step 10
9 | Use a J 39200 DMM in order to backprobe the underhood junction block. Measure the resistance between terminal A10 of connector C3 and ground. Is the resistance within the specified range? | 0-2 ohms | Go to Step 11 | Go to Step 12
10 | Repair the open in CKT 306 between the underhood junction block and the turn/headlamp switch assembly. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
11 | Use a fused jumper in order to backprobe the underhood junction block between terminal C11 of connector C3 and ground. Do the headlamps light? | -- | Go to Step 13 | Go to Step 14
12 | Repair the open in CKT 150 between the underhood junction block and ground splice pack G201. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
13 | Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
14 | Replace the underhood junction block. Refer to Relay/Fuse Center Replacement in Wiring Systems. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --