Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of your car that helps control the speed automatically. It's like when the remote control to your toy car stops working.
The code P0594 is set when the Engine Control Module (ECM) detects an open circuit in the cruise control servo control circuit.
The cruise control system uses a servo to maintain the vehicle's speed as set by the driver. The ECM monitors the servo control circuit for proper operation. If it detects an open circuit or an issue in the control circuit, it triggers the P0594 code.
• Cruise control not engaging
• Cruise control disengages unexpectedly
• Check Engine Light illuminated
• Faulty cruise control servo
• Damaged or corroded wiring in the servo control circuit
• Faulty ECM
ECM: Engine Control Module
Servo: A device used to control the speed of the vehicle in cruise control systems
• Use an OBD-II scanner to confirm the P0594 code.
• Inspect the cruise control servo and related wiring for damage.
• Test the continuity of the servo control circuit.
• Repair or replace damaged wiring in the servo control circuit.
• Replace the cruise control servo if faulty.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wiring repair tools
$100 - $500
Moderate
• Ford Focus
• Chevrolet Malibu
• Toyota Camry
• Regularly inspect and maintain vehicle wiring.
• Ensure the cruise control system is used properly.
• Have the vehicle serviced regularly.
Sensor Issue
• Avoid using cruise control until the issue is resolved.
• Have a professional mechanic inspect the vehicle.
Check with the vehicle manufacturer for warranty coverage on cruise control components.
The P0594 code has been associated with issues in vehicles with electronic cruise control systems since the early 2000s.
Moderate – The vehicle can still be driven, but cruise control functionality is impaired.
Operating a vehicle with a malfunctioning cruise control system can be hazardous. Ensure repairs are made promptly.
• Vehicle must be in motion.
• Cruise control system must be engaged.
The cruise control servo is typically located near the throttle body or within the engine bay.
Q: Can I drive my car with a P0594 code?
A: Yes, but the cruise control may not work properly. It's best to have it checked soon.
Q: Will the P0594 code affect my car's performance?
A: The main issue is with cruise control. Your car should drive normally otherwise.
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