OBD-II code · Network

U0142 Lost Communication with Body Control Module B

The Body Control Module B has stopped transmitting on the vehicle data bus, so other control units no longer receive its messages. A second body controller is silent; lighting, locks, or comfort functions can fail. Typical causes are loss of power or ground at the module, an open or shorted CAN/LIN bus wire, a connector fault, or an internal module failure.

Is it safe to drive with U0142?

Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.

Common causes

  • Most likelySecondary BCM unpowered
  • PossibleWater ingress into rear BCM
  • Less likelyGateway module routing CAN messages incorrectly

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
Hard
DIY friendly
Best left to a mechanic
Typical labour
1–6 h
Emissions test
Usually unaffected
Parts involved
Body Control Module, Can Bus Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.