All codes/U0012

U0012

Medium Speed CAN Communication Bus (-) Open

Moderate severity

The CAN-Low wire on the medium-speed comfort/body bus is open. Body modules such as door modules, climate control or seat modules lose communication, but powertrain functions usually stay alive.

The CAN-Low wire on the medium-speed comfort/body bus is open. Body modules such as door modules, climate control or seat modules lose communication, but powertrain functions usually stay alive.

Common causes

  • CAN-Low wire broken in body harness

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

    high

    Typical part cost: $70-550

  • Loose body control module connector

    A plausible cause — test and verify before replacing parts.

    medium

    Typical part cost: $70-550

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First things to check

  1. 1Confirm the code with a scan tool and check for additional related codes.
  2. 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does U0012 mean?

U0012 means "Medium Speed CAN Communication Bus (-) Open". It is a generic OBD-II code that points to a fault in the network / communication.

What are the most common causes of U0012?

can-low wire broken in body harness; loose body control module connector; gateway module routing can messages incorrectly — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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