All codes/P0493

P0493

Fan Overspeed

Moderate severity

Fan Overspeed: the control module has detected this fault condition.

Fan Overspeed: the control module has detected this fault condition.

Common causes

  • Fan relay welded closed - fan runs uncontrolled

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

    high

    Typical part cost: $90-440

  • PWM line shorted to supply

    A plausible cause — test and verify before replacing parts.

    medium

    Typical part cost: $90-440

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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 P0493 mean?

P0493 means "Fan Overspeed". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P0493?

fan relay welded closed - fan runs uncontrolled; pwm line shorted to supply; tachometer feedback miscalibrated — 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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