OBD-II code · Network

U0013 Medium Speed CAN Communication Bus (-) Low

The CAN-Low signal of the medium-speed bus is shorted to ground. Comfort and body modules can no longer exchange messages and trigger several user-visible faults at once (windows, locking, lighting).

Is it safe to drive with U0013?

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

Common causes

  • Most likelyCAN-Low shorted to ground
  • PossibleWater ingress in door connector
  • 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
0.8–5 h
Emissions test
Usually unaffected
Parts involved
Can Low Wire, Body Control Module

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