Park Brake Limited Function: Service Required. Why Do I See That?

Modern cars are quite different from olden-days cars. Though the functionalities are the same, features such as the steering, the braking, and the car's general maneuverability have improved over the years. All these new features are added, mainly for safety reasons and the vehicle's overall reliability.

Park brake limited function message highlights

• Common reasons:dying 12V battery, malfunctioning parking brake motor
• How to fix:check the battery, read the codes by scanner
• Possible consequences:car may not start
• Priority level:High
• Can you drive?Yes, if it starts
• DIY repair:Possible
• Repair price range:$200-$700

Understanding the park brake system

The parking brake is also known as the hand brake. It is used to keep the car motionless when it is parked. Depending on the car's make and model, you will find the parking brake to either be a foot pedal, a straight pull hand near the steering wheel, or a hand-pull lever. 

Car safety rules dictate that you use the parking brake whenever you have parked your car to prevent it from rolling. Besides using the parking brake to keep the car motionless, one can use the brakes at a traffic light or when moving off an uphill road.

Parking brakes employ a cable-pulling mechanism. For most cars, the parking brakes are on the rear wheels because they are with the least traction when braking. Since 2001, the mainstream car industry has embraced the electronic park brake.

This technology involves a motor that pulls the parking brake cable whenever you pull or push the park brake button. In some vehicles, the mechanism is a bit more complex because the motor attached to the rear calipers is computer controlled. It is called the Motor on Caliper (MoC) system.  

The button in the electric park brake system is mostly found at the center console. Just like in traditional cars that come with the pedal or hand-pulling levers, it is advisable to always leave your car in the Park gear before applying the parking brake. If your car is manual and you have parked it on a downhill road, put the car in reverse gear and then apply the parking brake.

'The park brake limited function: service required' error message

The park brake limited function: service required is a message to alert you about a problem affecting the parking brake system. It means that the system has detected a problem that requires service. Though the problem appears, some functionality is still available, but it is advisable to visit an authorized dealer at the soonest possible opportunity.

The electric park brake is much easier to use than the traditional park brakes. When you apply the parking brakes and leave the car, the car may automatically reapply the parking brake within the next ten minutes. This is a safety feature found in many modern cars. 

Your car can display the above error for several reasons. Many drivers who have reported the issue do so after using their cars in diverse weather and road conditions. Therefore, the issue can arise out of the blues, and the best thing to do is to be prepared.

1) The battery dies, and the error appears

Some drivers have reported that their car batteries have gone dead, and after replacing the battery, the park brake error message appears. In one case, the relatively new battery drained to 6 volts, and beyond recovery saw the driver encounter the park brake error after installing a new battery. 

When one starts the vehicle, a 'park brake limited function: service require' error message appears. Other error messages will appear, such as the 'park brake not applied/released' whenever you apply and release the brake. The later error message appears despite the driver hearing the parking brake engaging correctly. The parking brake works just fine despite the error messages appearing.

Solution:

It seems that once the battery gets drained or dies, the car's computer switches off too. This then means that when you install a new battery, the computer sends all sorts of errors because it is messed up. The solution is to erase the error codes.

Visit your dealership to have the error erased. If you have an ODB-II, you can erase the errors yourself. If the messages persist, it is time to do a proper diagnostic. But in most cases, it is just the ECN acting up, and sometimes, the error disappears on its own.

2) Corroded or worn-out park brake-related wire

The error message may appear when a wire associated with the braking system is damaged. The drivers who have pinpointed the error to damaged wires say that the error message appears intermittently, which becomes harder to solve.

The most likely culprit is the ABS wire found at the wheelbase of your car. This wire is insulated in a harness and a wiring loom on the outside. The wires mysteriously get cut even though they are insulated pretty well.

A logical conclusion to this is that the ABS wire gets cut because one end of the harness is attached to the moving axle, and the other goes into the ABS box. As you drive, the wheel reacts to the road, which means that one end of the wire is fixed while the other flexes many times as the wheels bounce or react to the road's condition. This leads to the wires cutting and only gaining contact intermittently hence the on-and-off error message.

Solution:

If the diagnostic machine shows an ABS issue, the first check will be the wire harness above the wheel, next to the shock springs. The best way to solve the wire problem is to replace it. But considering that the problem will recur, you might consider installing a different type of wire that will be less prone to cutting. Investing in a longer wire seems to work. Another suggested solution is to extend the already existing wire to lessen the pressure on it when the wheel reacts to the road.

3) Water

Drivers have reported experiencing this problem while driving in the rain or through puddles of water. Some specific car models seem to have this problem. This means that this could be a design failure because a vehicle should handle rain.

In other instances, the car might have an underlying problem, and water only serves to make it known to the driver. It could be that wires are exposed or corroded, and a splash of water exposes the condition.

Solution:

The best way to handle this problem is to have the car checked as the error message directs. The OBD-II should give the error codes of what exactly the problem is. Though it might sound ludicrous, for the cars that seem to develop this issue when driven through puddles of water, it might be wise to avoid such puddles where possible.

Steps to follow when the parking brake limited function message appears

There are instances when the error message will pop up, and you may not have a clue as to what might have caused it. The best thing to do is to run a first aid sort of diagnostic procedure. This way, the vehicle's computer will resolve the issue, and the error message will disappear.

• Start by turning the ignition ON. The engine should not start.
• Step on the accelerator pedal and push it all the way to the floor. Hold it on the floor.
• Lift the parking brake button up, which is setting the brake and hold.
• Turn the ignition to OFF and then ON within 5 seconds.

If the error message does not go away, then it means it is an actual issue, and the computer reset did not help. You should now visit a certified dealer to have the problem checked.

Conclusion

A Park brake system is very important in a car because it restrains the car when you park it. Neglecting this error message might lead to more serious problems. Even though you can drive while the 'park brake. Limited function: service required' error is showing; it is advisable to visit a mechanic to have the issue sorted as soon as possible.

The repair or correcting of this problem has no specific price tag because the issue could be anything from faulty ABS, a faulty caliper, or just a cut wire. Some drivers have spent $60 to have the problem sorted, while others have had to fork over more than $1,000.