All codes/P0594

P0594

Cruise Control Servo Control Circuit Open

Moderate severity

The servo motor that drives the cruise control throttle actuator has an open control circuit. The ECU cannot drive the servo - cruise control is unavailable.

The servo motor that drives the cruise control throttle actuator has an open control circuit. The ECU cannot drive the servo - cruise control is unavailable.

Common causes

  • Open in motor or harness

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

    high

    Typical part cost: $130-550

  • Pin pushed back out of connector body

    Less common, but worth ruling out after the more likely causes.

    low

    Typical part cost: $130-550

  • See all causes + fix costs

    Create a free Wrenchify account to unlock the rest for P0594.

    Unlock causes

    Free forever · No credit card

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.

Get the full step-by-step diagnosis

Create a free Wrenchify account to unlock the rest for P0594.

Unlock diagnosis

Free forever · No credit card

Related codes

See related trouble codes

Create a free Wrenchify account to unlock the rest for P0594.

Unlock related codes

Free forever · No credit card

Frequently asked questions

What does P0594 mean?

P0594 means "Cruise Control Servo Control Circuit Open". It is a generic OBD-II code that points to a fault in the vehicle speed, idle control, auxiliary inputs.

What are the most common causes of P0594?

open in motor or harness; pin pushed back out of connector body; cracked solder joint inside the module or sensor — 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.

Get the full P0594 diagnosis for your vehicle

Year, make, model + step-by-step repair help — free plan included.

Diagnose P0594