OBD-II code · Network

U0007 High Speed CAN Communication Bus (-) Low

The CAN-Low line is shorted to ground or held below its valid recessive level. The differential pair cannot transmit data and the bus is effectively dead.

Is it safe to drive with U0007?

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

Common causes

  • Most likelyCAN-Low shorted to ground
  • PossibleFailed transceiver on one module
  • 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
1–5 h
Emissions test
Usually unaffected
Parts involved
Can Low Wire, Can Transceiver

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