OBD-II code · Network
U0249 Lost Communication With Entertainment Control Module - Rear B
ECU lost communication with the rear entertainment control module B. A communication loss with this module breaks any function relying on its data — diagnostic tools may show 'no response' and dependent modules can fall into limp mode.
Is it safe to drive with U0249?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyModule unpowered
- Less likelyGateway module routing CAN messages incorrectly
- Less likelyCAN terminating resistor (120 Ω) drifted out of spec
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–4 h
- Emissions test
- Usually unaffected
- Parts involved
- Entertainment Module Rear B, Can Bus
Related codes
- U0246Lost Communication With Seat Control Module E
- U0247Lost Communication With Seat Control Module F
- U0248Lost Communication With Remote Accessory Module
- U024ALost Communication With Interior Lighting Control Module A
- U024BLost Communication With Seat Control Module G
- U024CLost Communication With Seat Control Module H
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.