OBD-II code · Network

U0017 Medium Speed CAN Communication Bus (+) Open

The CAN-High wire of the medium-speed bus is open. Body and comfort modules drop offline; the cluster typically displays multiple comfort warnings simultaneously.

Is it safe to drive with U0017?

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

Common causes

  • Most likelyCAN-High wire broken in body harness
  • 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
Hard
DIY friendly
Best left to a mechanic
Typical labour
0.8–4 h
Emissions test
Usually unaffected
Parts involved
Can High Wire, Body Control Module

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