Code result

U063F

Lost Communication With Engine Coolant Flow Control Valve Position Sensor

Moderate severity

What it means

The vehicle bus reports loss of communication with smart engine coolant flow control valve position sensor. Closed-loop control of the flow valve loses its actual feedback.

Is it safe to drive?

Use caution

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

  • Bus wiring open or shorted

    high

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

  • Module without power or ground

    medium

    A plausible cause — test and verify before replacing parts.

  • Module failed

    medium

    A plausible cause — test and verify before replacing parts.

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