Parking Brake not releasing

[gss2000]

Has anyone else had issue with the parking brake, just got my spark back from the dealer, i took it in because the rear brake was not releasing...they replace the rotor and pads, was driving it today and the car started to shutter, drove back home and the brakes were hot, i parked it, then went to move it to get my other car and when i released the parking brake the car would not move, the brake was still engaged, set the brake again and released it again, the car was able to move ...anyone else having issues??

 

[NomadMac]

I think I've had something similar happen, where it seems to get confused. Another time, I found myself going down my hill and picking up a lot of speed even though I was supposed to be in Low. A reboot of the car seemed to take care of both problems.

 

[Pegasus]

A reboot of the car seemed to take care of both problems.

Do you mean just stopping, turning it off, then turning it back on again, or something more drastic (disconnecting the 12V negative cable for a few minutes?)

 

[Nashco]

Has anyone else had issue with the parking brake, just got my spark back from the dealer, i took it in because the rear brake was not releasing...they replace the rotor and pads, was driving it today and the car started to shutter, drove back home and the brakes were hot, i parked it, then went to move it to get my other car and when i released the parking brake the car would not move, the brake was still engaged, set the brake again and released it again, the car was able to move ...anyone else having issues??

To be clear, did the light on the dash (parking brake applied indicator) turn off as though everything was normal and the brakes were released? Or was it not accepting your request to release it with the switch (and the light stayed on)?

I think I've had something similar happen, where it seems to get confused. Another time, I found myself going down my hill and picking up a lot of speed even though I was supposed to be in Low. A reboot of the car seemed to take care of both problems.

I would suggest these are very different issues! For example, a low traction/stability event could remove regen and not re-apply it until you are out of the event that would request regen deceleration (ie. you have reapplied the accelerator or applied the brake pedal).

Not releasing the parking brake properly would be a totally different cause/effect. It's interesting to keep track of, but not necessarily relevant to the original post IMO.

Of course, when a car with tons of electronics does something weird and a key cycle/power cycle/something else causes it to correct the failure, that's important to know and with enough examples of it occurring we can help provide specifics to GM so they can understand and correct it. Easier said than done!

Bryce

 

[NomadMac]

I meant a power cycle.

IIRC, the parking brake wouldn't respond to the switch to release, so I power cycled the car.The Spark was obviously stopped.

The no Low wasn't a traction issue. It appeared to indicate it was in Low but I had to use the brakes to control my descent, something I usually don't have to do and it was rapidly picking up speed, otherwise.

 

[Nashco]

I meant a power cycle.
The no Low wasn't a traction issue. It appeared to indicate it was in Low but I had to use the brakes to control my descent, something I usually don't have to do and it was rapidly picking up speed, otherwise.

How do you know there wasn't a momentary loss in traction? It only takes a pot hole to trigger the system to think there's a loss of traction, which removes regenerative braking and shifts to pure friction braking (based on my observations, not stating fact!). Was the battery power gauge displaying 0 kW when the brakes were applied and shifter was in L? What was your state of charge? Do you have floormats or something similar that could have held the brake and accelerator pedal at the same time? Did you drive for a while without any regenerative braking for an extended period (0 kW while applying the brakes and with the accelerator pedal released) or did you pull over immediately and cycle the power? Any other things you recall worth mentioning (weather, location, etc.)?

If we're talking about potential faults, the group can try to keep track to see if we notice a common theme. It makes these sorts of discussions much more beneficial.

I'm still not convinced these two problems are related, so it might still be better to have distinct threads for the two topics.

Bryce

 

[nozferatu]

Has anyone else had issue with the parking brake, just got my spark back from the dealer, i took it in because the rear brake was not releasing...they replace the rotor and pads, was driving it today and the car started to shutter, drove back home and the brakes were hot, i parked it, then went to move it to get my other car and when i released the parking brake the car would not move, the brake was still engaged, set the brake again and released it again, the car was able to move ...anyone else having issues??

It seems that the electronic brake on this car isn't something to write home about.

I take my sweet time releasing and engaging the brake...I always have my foot on the main brake when I am doing this to make sure the car doesn't roll.

When I do come to a stop on an incline and put the car in gear, no matter how hard I try, when I engage the parking brake and release the brake pedal, the car does roll..very annoying.

 

[gss2000]

I had it dropped off at the dealer today...will let you know what they say.

 

[gss2000]

Has anyone else had issue with the parking brake, just got my spark back from the dealer, i took it in because the rear brake was not releasing...they replace the rotor and pads, was driving it today and the car started to shutter, drove back home and the brakes were hot, i parked it, then went to move it to get my other car and when i released the parking brake the car would not move, the brake was still engaged, set the brake again and released it again, the car was able to move ...anyone else having issues??

To be clear, did the light on the dash (parking brake applied indicator) turn off as though everything was normal and the brakes were released? Or was it not accepting your request to release it with the switch (and the light stayed on)?

I think I've had something similar happen, where it seems to get confused. Another time, I found myself going down my hill and picking up a lot of speed even though I was supposed to be in Low. A reboot of the car seemed to take care of both problems.

I would suggest these are very different issues! For example, a low traction/stability event could remove regen and not re-apply it until you are out of the event that would request regen deceleration (ie. you have reapplied the accelerator or applied the brake pedal).

Not releasing the parking brake properly would be a totally different cause/effect. It's interesting to keep track of, but not necessarily relevant to the original post IMO.

Of course, when a car with tons of electronics does something weird and a key cycle/power cycle/something else causes it to correct the failure, that's important to know and with enough examples of it occurring we can help provide specifics to GM so they can understand and correct it. Easier said than done!

Bryce

Yes the brake light indicator on the dash would go off, though the brake was still engaged, seems like just the passenger side rear...

 

[gss2000]

Dealer replaced the Brake Module per GM recommendation - got the car back yesterday so far everything is OK...

 

[nozferatu]

Dealer replaced the Brake Module per GM recommendation - got the car back yesterday so far everything is OK...

was it a recall?

 

[gss2000]

Not that i know of...