Test Description
WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.
The numbers below refer to the step numbers on the diagnostic table.
- 2: Listen for an audible click when the DRL relay operates. Command both the ON and OFF states. Repeat the commands, as necessary.
- 3: This step tests for voltage at the coil side of the DRL relay.
- 4: This step verifies that the BCM is providing ground to the DRL relay.
- 5: This step tests if ground is constantly being applied to the DRL relay.
- 6: This step tests if there is opposing voltage present or an open in the DRL relay control circuit.
- 12: After replacement of the BCM, you must calibrate the new module for proper operation.
DTC B2600
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics Connector End View Reference: Lighting Systems Connector End Views or Data Communication Connector End Views |
|||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle |
| 2 |
|
Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 |
| 3 |
|
Go to Step 4 | Go to Step 10 |
| 4 |
|
Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 |
| 6 | Test the control circuit of the DRL relay for high resistance, an open, or a short to voltage. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
Go to Step 13 | Go to Step 9 |
| 7 | Test the control circuit of the DRL relay for a short to ground. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
Go to Step 13 | Go to Step 9 |
| 8 | Inspect for poor connections at the DRL relay. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
. Did you find and correct the condition? |
Go to Step 13 | Go to Step 11 |
| 9 | Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
. Did you find and correct the condition? |
Go to Step 13 | Go to Step 12 |
| 10 | Repair the DRL supply voltage circuit of the DRL relay. Refer to Wiring Repairs
. Did you complete the repair? |
Go to Step 13 | - |
| 11 | Replace the DRL relay. Refer to Relay Replacement (Attached to Wire Harness)
or Relay Replacement (Within an Electrical Center)
. Did you complete the replacement? |
Go to Step 13 | - |
| 12 | Replace the BCM. Refer to Control Module References
for replacement, setup, and programming. Did you complete the replacement? |
Go to Step 13 | - |
| 13 |
|
Go to Step 2 | System OK |