P0594 Fault Code

Cruise Control Servo Control Circuit / Open

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0594 fault code indicates an issue with the cruise control servo control circuit, specifically noting an open circuit condition. This means that the electrical connection to the servo, which controls the operation of the cruise control system, is disrupted. The cruise control system is essential for maintaining a steady vehicle speed without the need to keep your foot on the accelerator, enhancing driving comfort during long trips.

What are the symptoms of the P0594 code?

Symptoms related to a P0594 code may include:

• Inability to set or maintain cruise control speed.
• Cruise control system disengaging unexpectedly.
• Warning lights on the dashboard, such as the check engine light.
• Erratic or inconsistent throttle response while attempting to use cruise control.

What causes the P0594 code?

Common causes of the P0594 code include:

• Faulty cruise control servo.
• Damaged wiring or connectors within the servo control circuit.
• Issues with the vehicle's electronic control unit (ECU).
• Poor ground connections that affect the servo's operation.
• Blown fuses related to the cruise control system.

How to fix P0594?

To resolve the P0594 fault code, follow these steps:

1. Inspect the cruise control servo and its wiring for any visible damage or disconnections.
2. Test the cruise control servo for correct operation using a multimeter.
3. Repair or replace any damaged wiring or connectors.
4. Check and replace any blown fuses that apply to the cruise control system.
5. Clear the fault code and conduct a test drive to confirm the fix.