B2600

DTC B2600

CIRCUIT DESCRIPTION
The daytime running lights (DRL) are controlled by the body control module (BCM). The BCM grounds the DRL relay control circuit in order to energize the DRL relay coil. This action places the RH and LH headlamps in series with each other with the DRL relay providing the ground path and the RT HDLP fuse providing battery positive voltage. The BCM monitors the low and high beam circuits to ensure that the DRLs are operating properly. If the BCM senses that the DRLs are not operating properly, DTC B2600 is set.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B2600 Daytime Running Lamp Control 1 Circuit

CONDITIONS FOR RUNNING THE DTCs
- The headlamp switch is OFF.
- The park brake is unapplied.
- The transaxle is in gear.

CONDITIONS FOR SETTING THE DTC
One or more of the following conditions are present:
- The DRL relay control circuit is open.
- The DRL relay output circuit is open.
- The right headlamp battery positive voltage circuit is open.
- The left headlamp battery positive voltage circuit is open.
- The DRL relay ground circuit is open.

ACTION TAKEN WHEN THE DTC SETS
- The BCM turns OFF the DRL relay control for the remainder of the ignition cycle.
- The SERVICE indicator illuminates.

CONDITIONS FOR CLEARING THE DTC
- The conditions for setting the DTC are no longer present.
- A history DTC clears after 100 malfunction free ignition cycles.
- The BCM receives the clear code command from the scan tool.

DIAGNOSTIC AIDS
- Check both the LH and RH headlamps for proper operation.
- Check both the LH and RH HDLP fuses.
- Diagnose all other DRL DTCs before DTC B2600.
- If the DTC is a history DTC, the problem may be intermittent.

TEST DESCRIPTION

Steps 1-15:

Steps 16-20:

The numbers below refer to the step numbers on the diagnostic table.
2. DTC B2600 will disable the DRL. If the DRLs are operational the code is not current. If DTC B2600 is not current, refer to Diagnostic Aids for Circuit Testing and Wiring Repair Procedures.
3. This condition indicates that there is a short to voltage in the headlamp high beam signal circuit or the headlamp low beam signal circuit.
4. This step verifies normal headlamp operation.
7. This step checks for battery positive voltage at the coil side of the DRL relay.
8. This step verifies that the BCM is providing ground to the coil side of the DRL relay.