OBD-II code · Network

U0006 High Speed CAN Communication Bus (-) Open

The CAN-Low wire of the high-speed bus is open. The differential signal can no longer be evaluated correctly, so all bus participants report communication loss simultaneously.

Is it safe to drive with U0006?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyCAN-Low wire broken
  • PossiblePin pushed back in 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
1–6 h
Emissions test
Usually unaffected
Parts involved
Can Low Wire, Module Connector

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