For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Important: A short to ground will cause an open fuse(s). Before performing this diagnostic procedure, inspect the fuse(s) for an open.
1 |

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

Are all of the code setting conditions corrected?

--

Go to Step 2

Go to Step 3

2 |

1. Connect a scan tool to the data link connector (DLC).
2. Use the scan tool in order to command the daytime running lamps on.

Do the daytime running lamps (DRL) light?

--

Go to Step 3

Go to Step 4

3 | Replace the BCM. Refer to the following procedures:

• | Body Control Module Replacement in Body Control System

• | Body Control Module (BCM) Programming/RPO Configuration in Body Control System

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

4 |

1. Exchange the DRL relay with a known good relay from the underhood junction block.
2. Use the scan tool in order to command the daytime running lamps on.

Do the headlamps light?

--

Go to Step 5

Go to Step 6

5 | Replace the faulty relay. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
6 |

1. Remove the DRL relay.
2. Use a DMM in order to measure the resistance between CKT 589 terminal 87 of the relay connector and ground.

Is the resistance within the specified range?

0-2 ohms

Go to Step 7

Go to Step 8

7 | Connect a fused jumper between terminal B12 of connector C3 of the underhood junction block and ground. Do the daytime running lamps light? | -- | Go to Step 9 | Go to Step 10
8 |

1. Disconnect the DRL resistor.
2. Connect the DMM between terminal A and terminal B of the DRL resistor.

Does the resistance measure within the specified range?

0.25-0.75 ohms

Go to Step 11

Go to Step 12

9 | Repair the open in CKT 592 between the underhood junction block and the Body Control Module (BCM) . Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
10 | Replace the underhood junction block. Refer to Underhood Fuse Block Replacement in Engine Electrical. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
11 | Connect the DMM between terminal B of the daytime running lamps (DRL) resistor connector and ground. Does the resistance measure within the specified range? | 0-2 ohms | Go to Step 13 | Go to Step 14
12 | Replace the DRL resistor. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
13 | Repair the open in CKT 589 between the DRL resistor and the underhood junction block. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --
14 | Repair the open in CKT 1350 DRL resistor and ground splice pack G101. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Daytime Running Lights (DRL) System Check | --