Fault code P0588 is called “Cruise Control Vent Control Circuit High” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.
Technical description and explained code P0588
This diagnostic trouble code (DTC) is a generic code. Error P0588 is considered a generic code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly from model to model.
Cruise control was designed for comfort, the sole purpose of which is to maintain the vehicle speed set manually by the driver. The driver does not need to control the accelerator pedal.
If the car is equipped with an automatic transmission, he can control and adjust the shifts according to the driving conditions in real time.
There are many possible ways to control and operate the car’s cruise control system. One of the ways that manufacturers commonly use to control cruise control is with a vacuum-controlled system.
In most cases, a vacuum is used as an effective way to control the cruise control servo or similar membrane-type control. A vacuum control circuit is integral to the proper operation of this system.
These systems use a vent through which the ECM is able to regulate the vacuum in the system. The functionality of the vent is very important because it can sometimes directly affect the operation of the cruise control servo.
The servo is responsible for mechanically adjusting and controlling the speed when the cruise control is engaged. If the check reveals a current problem, the ECM will activate the cruise control code corresponding to the detected problem.
Fault code P0588 means that the cruise control ventilation circuit has a high signal level. It appears when a check performed by the ECM detects irregular electrical levels in the cruise control vent circuit.
Symptoms of vehicle malfunctions
The main signal that an error P0588 has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- Cruise control lamp on the dashboard is off or on all the time.
- Cruise control does not work completely.
- Unstable operation of the cruise control.
- Some functions do not work as they should (e.g. setting, resuming, accelerating, etc.).
- Cruise control turns on but does not work.
- Inability to adjust cruise control to desired speed.
- Whistling noises coming from the engine compartment.
Code P0588 has a low degree of severity, as it does not affect the safety and main assemblies of the car. But, like any electrical problem, it is better to eliminate it, so that the malfunction does not aggravate in the future.
Factors that can cause this error code
The error code P0588 can mean that one or more of the following problems have occurred:
- Vacuum leak or clogged cruise control system.
- The vent control solenoid is defective.
- Cruise control servo is defective.
- Cracked or broken vacuum hose.
- Debris and dirt is mechanically interfering with the cruise control servo.
- Wiring problem (breakage, chafing, etc.).
- Faulty connector (e.g. corroded contacts).
- Blown fuse.
- Defective cruise control module.
- Sometimes the cause is a faulty PCM module.
How to fix or reset OBD-2 code P0588
Some suggested steps for troubleshooting and fix the error code P0588:
- Connect an OBD-II scanner to the vehicle’s diagnostic connector and read all stored data and error codes.
- Clear the error codes from the computer memory and test-drive the vehicle to see if code P0588 appears again.
- If the code appears again, check the wiring and related connectors. Make sure they are not broken or frayed. Repair or replace if necessary.
- Inspect and test vacuum lines.
- Check the operation of the vacuum solenoid as well as the cruise control servo.
- If there are no faults, the cruise control module or PCM may be defective.
Diagnose and repair of problems
The first step in the P0588 troubleshooting process is to review the Technical Service Bulletins (TSB). For known problems with a particular vehicle.
Next, open the hood to check the cruise control system. Trace where the vacuum control line goes and what it controls.
If it goes directly to the vacuum solenoid, carefully inspect the vacuum lines, solenoids, and cruise control servo for physical damage. Any damage found must be repaired or replaced before further diagnosis.
Check the electrical parameters of the vacuum cruise control solenoid to rule out the possibility of an internal fault. If outside manufacturer’s limits, replace solenoid, reset error and test drive.
Check the vacuum in the system using the outlets in the intake system designed for this purpose. These are usually located on the intake manifold itself, but consult the manual for details.
Normally the vacuum reading should be about 50-55kPa at operating temperature and proper ignition setting.
A problem with the PCM module is in most cases a last resort to diagnose error P0588. Considering the fact that it can be one of the most expensive repairs, it is better to entrust it to professionals.
On which vehicles does this problem occur most frequently
Fault code P0588 can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- Audi
- Chevrolet
- Chrysler
- Dodge (RAM)
- Honda
- Hyundai
- Jeep
- Volkswagen
Fault code P0588 can sometimes be found with other errors. The most common are the following: P0582, P0583, P0584, P0586, P0587.
