DTC P1555: Control Unit Function Monitoring, Wake-Up: Notes

Diagnostic information - DME (DFI) control unit 

INFORMATION 

• The entered fault code P1553 or P1555 is merely an indication that the DME control unit performed a reboot in its internal monitoring unit when starting the engine.
• This normally remains unnoticed by the driver!
• In the event of a customer complaint  reporting that manual engine starting (starting with the key)  was refused, was aborted or took too long, the DME control unit is faulty.
• If no such customer complaint  exists, the DME control unit is OK!