Diagnostic Aids
- If the DTC B2577 is a history DTC, the fault may be intermittent. Refer to TESTING WIRING SYSTEMS FOR INTERMITTENT & POOR CONNECTIONS
- The following conditions may cause an intermittent malfunction to occur:
- An intermittent short to ground or open in the headlamp relay control circuit.
- The headlamp relay coil is intermittently shorted to ground or open.
- The BCM is intermittently shorted to ground or open.