Operation CHARM: Car repair manuals for everyone.

B2603

DTC B2603

CIRCUIT DESCRIPTION




The daytime running lights (DRL) relay is controlled by the body control module (BCM). Battery positive voltage is applied to the relay coil at all times. The BCM grounds the DRL relay control circuit in order to turn ON the DRL relay. When the DRL relay control circuit becomes shorted to battery positive voltage, DTC B2603 is set.

CONDITIONS FOR RUNNING THE DTC
The ignition switch is in the ON position.

CONDITIONS FOR SETTING THE DTC
- The BCM is commanding the DRL relay on.
- The headlamp feedback is not present for 1 second.

ACTION TAKEN WHEN THE DTC SETS
- The BCM disables the DRL relay control as long as the malfunction is present.
- 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
- The park brake must be unapplied and the transaxle must be in gear for the DRLs to operate properly.
- If the DTC is a history DTC, the problem may be intermittent.

TEST

Steps 1-10: