A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
U1556 ← What does this code mean?2 Results
CHEVROLET, GMC · 2017-12-21
This Preliminary Information communication provides information to the technician about vehicles that have Trailer connection not recognized or “Check Trailer wiring” or “Service Trailer Brake” message. Technician may find Diagnostic Trouble Codes C1112, C1113, C1114, C111B, U1556, and/or U1505. Technician will need to inspect the battery and Trailer Brake Power Module connector for corroded terminals and replace as necessary.
CHEVROLET, GMC · 2016-11-18
This Preliminary Information communication provides information to the technician about vehicles that have Trailer connection not recognized or ?Check Trailer wiring? or ?Service Trailer Brake? message. Technician may find Diagnostic Trouble Codes C1112, C1113, C1114, C111B, U1556, and/or U1505. Technician will need to inspect the Trailer Brake Power Module connector for corroded terminals and replace as necessary.