The electric parking brake is one of the best driver aids we can find in modern cars. Mainly because they help you will hill starts, but also because there is no risk of hand brake cables snapping. But that doesn’t mean the electric brake can’t go wrong. After all, it is a much more complicated design.
The two main problems with electric parking brakes are that they won’t engage, or that they won’t disengage. The possible causes for both include a bad battery, bad caliper motor, bad control module, wiring issues, blown fuse, or a bad parking brake switch.
Common Problems With the Parking Brake
Parking Brake Won’t Engage
The most common problem with the electric hand brake is that it won’t engage automatically, or when you press the button. There is also a chance that the brake engages but it doesn’t hold the vehicle, or it doesn’t hold the vehicle well enough. When you come across this problem, make sure to always leave the transmission in Park and only leave the car on a level surface.
The causes of this problem can be any one of those that we will go into. But most commonly it’s a bad brake caliper motor, a blown fuse, and a bad battery. Troubleshooting this problem is pretty easy as long as it’s one of those three causes. Otherwise, you will have to visit a repair shop to get a proper diagnosis.
Parking Brake Won’t Release
The parking brake not releasing is a fairly common problem on cars made in the last ten years or so. When the brake refuses to disengage, you won’t be able to drive the car. And even if the car moves when you press the gas pedal, you can cause thousands worth of damage if keep driving the car. You can destroy the brake caliper, rotors, brake pads, boil the brake fluid, destroy the tires, etc.
It’s important to mention that even though any of the problems below can be the cause, it rarely is. This is mostly caused by a glitch in the control module. Solving this is usually done with a special procedure that goes something like holding the button down for a couple of seconds, releasing the brake pedal, and pressing the gas pedal.
But the procedure is different for every car so you can contact the dealer to see what it is for your car, or visit some model-specific forums to see if anyone has figured it out yet. Alternatively, you can disconnect the negative battery cable for a couple of minutes to reset the control module. That’s a universal fix that has worked for a lot of people.
Parking Brake Problems – Causes & Fixes
1. Old or Faulty Battery
The electric parking brake uses an electric motor to engage or disengage the parking brake mechanism. Some cars have a separate caliper for the hand brake, and in others, it’s an integrated system. Whatever the case, that electric motor uses power from the car battery to operate. If the battery is drained or old, the voltage going to the motor won’t be high enough or consistent enough.
When that happens, the control module will disable the electric motor to prevent damage and throw different fault codes. It’s worth mentioning that a standard car battery lasts around three to five years. There is also a chance that the charging system is bad which would cause the battery to drain.
To check if this is the problem, you can test the battery and the alternator using a multimeter. But if you visit any AutoZone or NAPA store, they will test the battery and the alternator for free, as well as scan the fault codes. If it turns out the battery is bad, expect to pay anywhere between $100 and $250 for a new one depending on the size and type.
And if the charging system is bad, a new alternator costs $300 on average with labor and parts. There is also a chance that the voltage regulator is bad, in which case it will cost around $100 to $150 with parts and labor.
2. Bad Brake Caliper Piston or Electric Motor
The electric motor in the electric parking brake system is the single most important component. If it fails, the motor won’t engage or disengage the hand brake. You will also get corresponding fault codes with it which you can scan with an OBD2 Bluetooth reader if you don’t feel like visiting an AutoZone or NAPA store.
You can also test the motor by bypassing the electric connector which is something shade tree mechanics do to retract the piston when replacing brake pads. But you can cause damage doing that, and you need a wiring diagram for your car.
If it turns out the motor is bad, expect to pay around $150 to $300 for a new one. Replacing it is fairly easy so the labor won’t be that bad at one hour or so which is another $100. But since the new motor does require calibration, it’s not something you can do at home. Although you might get away with replacing the motor at home and having it calibrated at a shop, I can’t guarantee it will work.
3. Bad Parking Brake Switch
The parking brake switch isn’t an all-too-common failure. But it is easy to diagnose. Most cars will put the electric handbrake on as soon as you shut down the vehicle. And the car will also disengage the hand brake as soon as you put the transmission in Drive and press the gas pedal.
If the hand brake works under those conditions but not when you push the button, then there is your problem. If you are not sure that the brake is engaging when you turn the engine off, have someone by the rear wheel to listen for a buzzing sound once to shut the engine down. The buzzing sound means the motor is working and the brake is engaged.
How much a new button will cost depends on the car but it’s safe to say they are around $30 for a non-OEM one or a used one. An OEM button at the dealer will cost closer to $100. Replacing it only takes about five minutes since it pops out of the console, and you can easily replace it yourself.
4. Bad Control Module
The electric hand brake communicates with pretty much all the modules in the car. That means it has to have its own electronic module or has to run off an integrated module. That could be a body control module, ABS module, transmission control module, or engine control module. And if the module the parking brake is operating through fails or glitches, it won’t work properly.
Unfortunately, diagnosing a control module is pretty difficult since that’s what’s supposed to tell you what’s wrong through fault codes. But it won’t be a big problem for the dealership or a seasoned third-party mechanic. If the module turns out to be faulty, a new one will set you back around $200 to $500.
But I suggest you get a used one because these modules virtually never fail making it a safe buy. Plus, a used module shouldn’t cost more than $100 in most cases. And if you want to be extra safe, buy one locally from a private seller or at a breaker yard.
5. Poškození elektroinstalace
Wiring damage is an extremely uncommon cause of electric parking brake problems. But it can still happen, especially if the car has undergone a significant repair in that area or if the car has been in an accident. Another problem is that the electric motor connector sits behind the wheel so it’s exposed to salt, water, mud, dust, etc.
Even though the connector is well insulated, damage can still happen. To check if that’s the case, disconnect the plug and see if it looks dusty or corroded. If it does, use some contact cleaner spray and a wire brush to clean it up. Then let it dry and reconnect it. As for wiring, follow the wires coming off the connector and inspect them carefully.
If you find any breaks in the insulation, cut out that piece of wire and replace it with a new one. Make sure to insulate that part with some shrink tube. If you run into problems again, have a professional do it or replace the entire wiring loom.
6. Spálená pojistka
Like all electric parts that use a lot of power, the electric parking brake motor has a fuse. If the fuse burns out, the hand brake won’t engage on disengage depending on where it’s stuck. You will also get corresponding warning lights or messages on the dashboard. To check if it’s the fuse, break out your owner’s manual.
There you will find the location of both fuse boxes in the car, together with a diagram of both. Go through the functions of each fuse until you find one for the hand brake then pull it out and check if the metal piece inside is broken. If yes, replace the fuse with a new one of the same amperage and you are good to go.
How Reliable Are Electric Parking Brakes?
Generally speaking, electric parking brakes are much more reliable than conventional cable-operated hand brakes. Pretty much the only thing that goes wrong on an electric parking brake is the electric motor and even that is supposed to last the lifetime of the vehicle. Hand brakes on the other hand need to be frequently adjusted, the cables replaced and the mechanism refreshed.
How Do I Reset My Electronic Parking Brake?
Resetting the electronic parking brake is usually done with a special procedure that’s only known to the dealer. But you can check some forums to see if other owners have figured it out. You can also disconnect the negative battery cable which usually works, or you can have someone reset it using a professional OBD2 scan tool.
What Are the Disadvantages of Electric Parking Brakes?
The main disadvantage of an electric parking brake is that you can’t fool around with it and do slides in an empty parking lot. And on the off chance that your brakes fail while driving, you can’t use the hand brake to slow down because it won’t engage. But other than that, the electric hand brake is miles better than a conventional one, especially for the average driver.
Is the Electronic Parking Brake the Same as the Handbrake?
The electronic parking brake is essentially the same as the hand brake. Both the parking brake and hand brake lock up the rear wheels of the car using brake calipers or drum brake shoes. The only difference is that the hand brake is operated via cables attached to the hand brake lever, and the electric hand brake is operated using electric motors.
How Long Do Electric Car Brakes Last?
Electric car brakes should last at least 100,000 miles unless they have some known factory defects. During that time, the electric brake doesn’t require any servicing other than replacing the brake pads. Some components might fail earlier but that’s uncommon. On a conventional hand brake, during those 100,000 miles, you would have to adjust the hand brake cables multiple times, and even replace them once or twice.
What Are the Two Types of Electric Parking Brakes?
The two types of electric parking brakes are motor-operated, and cable-operated brakes. The cable-operated system works just like a conventional hand brake but in this case, an electric motor pulls the cables. But this system is only present on mid-2000s cars that still had an optional standard hand brake. An electric motor-operated brake doesn’t have cables and the motor sits on the brake caliper itself.
Závěrečná slova
If you are having problems with your electric hand brake, the first thing you should do is check the fuse, parking brake switch, and car battery. Those three are extremely easy to inspect and you will know for certain if one of them is the cause.
Should that not help, it’s best to have the fault codes scanned by the dealer or a reputable third-party shop. That’s because diagnosing a bad electric motor, control module, or wiring can be difficult or even impossible for an amateur mechanic.
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