I had an issue with my Emergency brake being stuck on yesterday. Temps in the mid teens, with the car parked outside at a business for 4 hours. I have never had an issue with this before. I have searched and read every thread on Emergency/Parking brake issues and have not found one that matched mine.

I came out of an office after a 4 hour meeting to discover that the parking break would not disengage. I have no errors on the dash, no warning lights, no codes in torque. The car will still move, but it clearly isn't happy about it. I tried to rock it back and forth small distances in hopes of releasing the stuck brake. No joy in that.

Lucky for me this place has a complete service bay for working on their fleet vehicles. I was able to move it into the service bay. Both rear wheels were impacted, but when we used a large screwdriver (without significant effort) to make the driver rear brake release, all was good. The brakes would engage and disengage correctly at that point, both using the brake pedal as well as the automatic parking brake system.

On to my next appointment, and 4 hours later I had the same issue. I had the car towed to my house and limped into the unheated garage. Again no codes or warning messages from the car, just an engaged Emergency brake. 2 hours later I went out to check on it and the brakes were released already and the system engaged and disengaged as it should. I used information I learned here to push on the parking brake switch while shutting off the car and removing the key in order to have it sit over night not engaged. While the garage is not heated, it is attached to the house and is probably 20-30 degrees warmer than outside.

The sun is up this morning and I am ready to attempt to tackle this issue. I am hoping the solution to this is some sort of spray lubricant. Or do I have cables that need to be replaced? I am assuming that it isn't the electric motor that draws and releases the cables as that seems to work fine when the brakes are not locked up.

Any advice?

 

A follow up:

Took a good look at it today. In the warmth of the garage the EPB works as it should. When releasing the EPB the motor appears to function as it should be the cable seems a bit sluggish as it is push back out. The motor seems to have no problem retracting the cable and applying the brakes.

I am thinking of taking it to my indy and having him use a cable lubrication tool and lubing the cable. Anyone see an issue with doing this? Any "special" lub I should use?

 

Hello Wheelgun, haven't seen you on here for a bit ! I think you bought your car near the same time as me, 2010, correct ? How is the car going ? Mine is now on 89k,but has not been issue-free, although always reliable. I've never been left at the roadside.

If you can replace just the cable on its own, that is what I would do, but some lube will do no harm. I would use a fairly thin engine oil, like the same as one adds to the engine. This means in cold weather, it won't get waxy and hinder the cable movement. Lubing may only be a temporary solution, as sometimes the cable inner just wears away and you get too much friction in the cable.

Other thing that does freeze up is the mechanism inside the caliper. I had this early this year, and wore out a disc and pads, ending up needing new discs, pads, and a new OS caliper. Not cheap !!

 

Hi 45Wheelgun,

It might be worth cleaning the electrical connectors for the EPB motor - not real easy to access but they live in a harsh environment under the car and may be vulnerable to corrosion. Any additional resistance in the circuit could be messing with the motor's operation in one direction, especially if there is also mechanical resistance in the cables, levers, etc.

Regarding lubing the cable, in general if a cable is unjacketed there may be no harm in lubing it, but if I'm not mistaken, part of the EPB cable rides within an outer jacket. If that is the case, you may not want to use oil or grease since they can attract and hold dirt, grit and other grunge that can worsen the function of your cable. It might be worth trying one of the graphite lube sprays that evaporate to a dry film and would be less likely to attract more contaminants.

You might also try cleaning the moving parts at the brake caliper and perhaps lubricating them with dry graphite too.

Please let us know what you decide and how it goes.

Cheers,

Don