Code result

U0005

High Speed CAN Communication Bus High

High severity

What it means

The CAN-High line is held above its valid voltage range, usually because of a short to battery voltage. Bus communication collapses for every connected module.

Is it safe to drive?

No — stop driving

This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.

Most likely causes

  • CAN-High shorted to battery voltage

    high

    One of the most commonly reported causes for this code — check this first.

  • Chafed harness against power wire

    medium

    A plausible cause — test and verify before replacing parts.

  • Gateway module routing CAN messages incorrectly

    low

    Less common, but worth ruling out after the more likely causes.

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