P0595 OBD-II Trouble Code: Cruise Control Servo Control Circuit Low

check engine light

P0595 trouble code definition

A P0595 trouble code is related to a vehicle’s cruise control servo that helps a vehicle maintain speed automatically. If the engine control unit detects voltage or resistance from the cruise control system, it will test the entire system - determining the cruise control servo control circuit is low on voltage to trigger a P0595.

What the P0595 code means

P0595 is an OBD-II generic code for a low voltage problem with the cruise control servo control circuit in that the signal being sent to the engine computer is not within the manufacturer’s parameters.

What causes the P0595 code?

A P0595 code can have more than one cause, but the most common are:

  • Faulty cruise control servo solenoid
  • Faulty cruise control switch
  • Faulty cruise control servo
  • Faulty cruise control circuit wiring
  • Faulty cruise control connectors
  • Faulty fuse

What are the symptoms of the P0595 code?

A P0595 will usually cause the cruise control to work poorly, or not at all. Some vehicles will also illuminate a cruise control light with the Check Engine Light.

How does a mechanic diagnose the P0595 code?

Your mechanic will first clear the code to see if it returns immediately. If it does, a visual inspection of the cruise control system will be next, paying close attention to the servo itself. If wiring or connectors appear damaged, they will need to be replaced. All vacuum lines to the cruise control servo will need to be inspected and repaired as well. The cruise control fuse will also need to be inspected for damage. If the problem continues, the cruise control switch and servo solenoid will need to be tested for continuity before being replaced. In some cases, the servo itself will not work and will need to be replaced.

Common mistakes when diagnosing the P0595 code

Hastily replaced components can result in unchanged results, so it’s important to test components before parts are replaced.

How serious is the P0595 code?

Because the worst that can result from a P0595 is the cruise control not working, the code isn’t very serious and your vehicle can be safely driven until repaired.

What repairs can fix the P0595 code?

The most common repairs for a P0595 are as follows:

  • Replaced cruise control servo solenoid
  • Replaced cruise control switch
  • Repaired cruise control circuit wiring
  • Replaced cruise control fuses

Additional comments for consideration regarding the P0595 code

Some vehicles have different styles of cruise control servos and it depends on whether or not your vehicle is drive-by-wire. These are controlled by the same actuator that opens and closes the throttle.

Need help with a P0595 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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