U0249Lost Communication With Entertainment Control Module - Rear B
- Generic OBD-II code · Network
- How the car detects it
- Rear B is the second rear entertainment unit; GM applies the code to a concrete part. Its 2011 Saab 9-5 code list names U0249 as lost communication with the rear radio audio control module, the rear seat audio controls with their own headphone outputs. On 2013–2014 Buick Enclave, Chevrolet Traverse and GMC Acadia the radio and the HVAC module stored U0249 within a long list of U codes when the side object sensor harness at the right rear rubbed through on the muffler and disturbed the LAN wiring; the cure was repairing and rerouting that harness (PI1202). The case shows that one chafed lead can silence modules far from the damage. Without unit B, rear audio controls, headphone sound or the second rear screen stop. Rear unit A is U0196, invalid data from B U054A.
- What you may notice
- Rear audio controls or headphone outputs dead
- Second rear screen without picture
- Many U codes across modules, radio may switch off while driving
- Likely causes
- LikelyChafed or burnt network wiring elsewhere in the vehicle (GM: harness on muffler)
- PossibleRear unit without power or ground
- PossibleLoose or corroded connector at the rear unit
- RareRear unit internally faulty
- Repair
- Medium · Usually a job for a workshop.Typical cost: €0 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.