U1255, Generic Loss Of Class 2 Devices: Testing
- Clear DTCs and cycle ignition. Check for DTCs. If DTC U1255 exists, use scan tool to establish communications with each module on Class 2 data bus. Repair or replace as necessary. Ensure Class 2 serial data line is not shorted to ground or battery (DTC U1300 or DTC U1301 would be set). If circuit and individual modules are okay, replace BCM.