OBD-II Code P0586 — What It Means & How to Fix It

What Does This Error Mean?

P0586 means there is a problem with the cruise control vent solenoid circuit. Older vacuum-actuated cruise control systems use a vent solenoid to release vacuum and reduce throttle when you decelerate. When this solenoid circuit fails, the module cannot properly control cruise control speed reduction. Cruise control will be disabled as a safety precaution.

Affected Models

Vehicles 1996–2010 with vacuum-actuated cruise control
Common in older Ford Mustang and F-Series
Common in GM vehicles with cable-type throttle
Common in Dodge trucks with older cruise modules
Rare on vehicles with electronic throttle control (drive-by-wire)

Common Causes

Failed vent solenoid inside or attached to the cruise control actuator
Open circuit or broken wire in the vent solenoid control circuit
Corroded connector at the cruise control actuator preventing solenoid operation
Blown fuse protecting the cruise control vent solenoid circuit
Defective cruise control module unable to activate the vent solenoid output

How to Fix It

Start by checking the cruise control fuse. Consult your owner's manual or the fuse box diagram under the hood to find the correct fuse.

A blown fuse costs less than a dollar to replace and is always worth checking first.
Locate the cruise control actuator in the engine bay, usually mounted on the firewall. The actuator typically has two vacuum ports and one or two electrical connectors.

The vent solenoid may be a separate connector or integrated into the main actuator connector depending on the vehicle.
Inspect the actuator connector for corrosion or damaged pins. Clean with electrical contact cleaner and reconnect firmly. Clear the code and test if cruise control works.

A simple connector cleaning fixes more faults than most people expect.
Test the vent solenoid resistance with a multimeter. Disconnect the solenoid connector and measure resistance across the solenoid terminals. An open circuit (infinite resistance) confirms solenoid failure.

Typical solenoid resistance is 20 to 60 ohms — check your service manual for the exact spec.
Replace the cruise control actuator if the solenoid tests faulty. After replacement, clear the code and verify cruise control sets, holds, and releases speed correctly.

When replacing the actuator, also inspect the vacuum hoses. Old, brittle hoses should be replaced at the same time to prevent a repeat fault.

When to Call a Professional

The vent solenoid is usually part of the cruise control actuator assembly. On most vehicles, if the solenoid fails, the entire actuator needs to be replaced. Actuators range from $50 to $150 for the part, plus one to two hours of labor. Total repair cost at a shop is typically $150 to $300.

Frequently Asked Questions

What does the vent solenoid do in a cruise control system?

In a vacuum cruise control system, engine vacuum holds the throttle open at the set speed. The vent solenoid releases that vacuum to allow the throttle to close when you reduce speed or disengage cruise control. Without a working vent solenoid, the system cannot smoothly reduce throttle, which is a safety problem.

My car has drive-by-wire — can I still get P0586?

P0586 is primarily associated with older vacuum-actuated cruise control systems. On modern drive-by-wire vehicles, the cruise control works differently and this specific solenoid does not exist. However, some manufacturers use P0586 for other cruise control circuit faults on newer platforms — check a database specific to your vehicle.

How long can I drive with P0586?

You can drive indefinitely with P0586 — cruise control will simply not work. There is no risk to the engine or drivability. However, address the fault when convenient as a fully functioning cruise control improves highway safety and fuel economy.