All codes/U0678

U0678

Lost Communication With Fuel Level Sensor C

Moderate severity

The vehicle bus reports loss of communication with smart fuel level sensor C. Tank gauge may freeze and low-fuel warnings may be incorrect.

The vehicle bus reports loss of communication with smart fuel level sensor C. Tank gauge may freeze and low-fuel warnings may be incorrect.

Common causes

  • Bus wiring open or shorted

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

    high

    Typical part cost: $130-1100

  • Module without power or ground

    A plausible cause — test and verify before replacing parts.

    medium

    Typical part cost: $130-1100

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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 U0678 mean?

U0678 means "Lost Communication With Fuel Level Sensor C". It is a generic OBD-II code that points to a fault in the network / communication.

What are the most common causes of U0678?

bus wiring open or shorted; module without power or ground; module failed — 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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