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U3563: Cathode Bypass Valve Position Sensor Circuit

What Does U3563 Mean?

U3563 is a diagnostic trouble code indicating: Cathode Bypass Valve Position Sensor Circuit. This code relates to the vehicle systems system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

What To Do Next

  1. 1
    Find your vehicle above

    Click your make and model for real owner reports and common causes specific to your vehicle.

  2. 2
    Check for recalls

    Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.

  3. 3
    Get a professional diagnosis

    A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

Related Codes

U3558 Hydrogen Tank C Valve U3559 Air Inlet Pressure Sensor Circuit U3560 Cathode Backpressure Valve Position Sensor Circuit U3561 Cathode Bypass Valve Control Circuit U3562 Cathode Bypass Valve U3564 Hydrogen Supply Line A Pressure Sensor 1 Circuit U3565 Hydrogen Supply Line A Pressure Sensor 2 Circuit U3566 Anode Inlet Pressure Sensor 1 Circuit