All codes/C0021

C0021

ABS Pump Motor Circuit Range/Performance

Moderate severity

The pump motor responds, but its current draw or run time is outside the expected range. The control module suspects mechanical wear or hydraulic blockage.

The pump motor responds, but its current draw or run time is outside the expected range. The control module suspects mechanical wear or hydraulic blockage.

Common causes

  • Pump worn, low delivery

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

    high

    Typical part cost: $440-1760

  • Hydraulic block contaminated with brake fluid debris

    A plausible cause — test and verify before replacing parts.

    medium

    Typical part cost: $440-1760

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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 C0021 mean?

C0021 means "ABS Pump Motor Circuit Range/Performance". It is a generic OBD-II code that points to a fault in the chassis.

What are the most common causes of C0021?

pump worn, low delivery; hydraulic block contaminated with brake fluid debris; sensor element aged beyond calibration window — 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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