Park Brake Interlock

The park brake interlock is a safety system that stops you from putting the vehicle in gear unless the brake pedal is depressed. But what if you put your foot on the brake and it does not come out of park?

Not only have I received a lot of questions about this common shifter problem I have also seen it on the vehicles that I work on locally. Since the mid 90’s all vehicles now come equipped with a park brake interlock system.

This is a great safety feature that requires you to have your foot on the brake pedal before it will allow you to shift from the park position to your desired gear. This system operates by a switch on the brake pedal that intern operates a interlock solenoid on the shifter mechanism.

When you apply the brake the solenoid pulls the shifter lock out of the way to allow free shifter movement. Some vehicles are equipped with a cable that is activated by a solenoid mounted on the brake pedal. Either system will release the safety lock on the shifter that allows you to move it from the park position.

When the park brake interlock system malfunctions the vehicle will of course not move. The first reaction for many car owners is to start pushing and pulling on the release button and pulling hard on the shifting mechanism handle itself. This is not a good idea because most of these parts are made of plastic or white metal that will crumble when large amounts of force applied.

Often when I diagnose this system, I will find that the solenoid is not pulling the cable and therefore the release mechanism is not disengaging from the shifter. What I have found most often is spilled soda or coffee causing a sticky situation. Most center consoles contain a cup holder near the shifter.

It is very common that a drink will spill in this area and damage the park brake interlock solenoid. The owner will clean the area, but may not realize that soda has dripped inside the shifting mechanism and on the solenoid. 

The console that surrounds the shifter is usually very easy to remove. You can consult your auto service manual for exact location of the hold down screws (sometimes they are hidden).

After the console has been removed you can clean the area with alcohol or basically any type of cleaner, and the system should begin to work properly again.

What happens if cleaning the parking brake interlock does not work? Well if the solenoid or the cable mechanism is broken and not repairable there is an emergency safety override.

Often this is located at the base of the shifter mechanism near the cable are solenoid. Check your vehicle specific owner’s manual for the location of your emergency release and how to operate it.

Or ask a mechanic that knows where it is on your specific model car.

Usually the interlock override will allow you to push a button and release the park brake interlock manually. This way the automobile can be moved or taken to the auto service facility.