R8Z51

Hi folks,

I've noticed my electronic parking brake automatically comes on when I go to start the car up. I have never turned it on manually. Is this some sort of a safety feature? It's done it 3-4 times now.

WelderGuy

It comes on automatically every so often to check the operation of the system.

golden2husky

Yep, mechanical atrophy is as bad as physical atrophy for a human. If the system went unused for a few years it might no longer engage, or worse, disengage. Use the parking brake on all of your cars at least periodically.

Larry/car

Good find. The parking brake system is so simple I just breezed over it and missed the auto on part. I'm bad!

R8Z51

Good to know. Thanks guys!

defaria

It's never come on automatically for me. I have an M7, if that matters.

R8Z51

The weathers below freezing here so it might only do it at certain temperatures to prevent it from binding up.

Flame Red

Inquiring minds gots to know...

I have never seen it come on by itself and I rarely use the parking brake. But I live in the Florida Inferno, so perhaps it does have something to do with temperature?

So I checked the Helms service manuals and under the Parking Brake System Description, there is no mention of it having the capability to apply itself - except as part of the M7 Hill Assist feature. Is the OP an M7 and perhaps it is somehow sensing it is parked on an incline and using Hill Assist?

Smart Line

Mine turns it self off i like that feature.
M7

R8Z51

My car is a 2014 with the A6 transmission.

joemessman

I have noticed on mine that periodically, not often, when I got to start the car it displays something indicating the parking brake is on. I didn't ever remember engaging it. I didn't realize it did it automatically once in a while. Learn something new about the car everyday.

DAFFYDRUNK

Mine has never come on automatically but I use it all the time. It must only do this if its not used.

joemessman

I'll bet that's it. I never have to use mine. I never seem to park on any hills.

R8Z51

Is it necessary to use the parking brake when parking on an incline or decline?

DAFFYDRUNK

Probably not, but I use it in automatic cars if the hill is steep. Apply it before putting the car in park and releasing the brake, then when leaving, put the car into gear before releasing the ebrake to make getting out of park a little easier.
On manual trans cars, I use the ebrake all the time because I once had my old 96 TA pop out of gear and roll into the street where it magically hit a soft mattress a neighbor left out for trash pickup that morning. If the mattress wasn't there they would've been fishing the car out of a creek.

owc6

If you park an automatic on an aggressive incline w/o the parking brake, it it's possible to torque lock the transmission.

When this happens there is so much stress on the locking pawl that you can not get the car out of park, which requires the car to be pushed uphill to release the shifter. To avoid this, when parking on a hill, do as daffy says and apply the parking brake Before shifting to park.

pickleseimer

On a side note, on the automatic transmissions I've had apart, I frankly am skeptical of the parking pawl mechanism. To think that this usually rather small part actually holds the entire car in place, including inclines, seems insufficient. Yes, I know the engineers have figured it out, and no I haven't seen the specific parts in the Vette's A6 or A8 yet, but I've been setting the parking brake in every car I drive, manual or auto, since way before I started using seatbelts lol

Foosh

The parking brake has always been engaged on every car I've driven for decades. It's a simple precaution, a habit for me like the shoulder harness, and it saves wear and tear on the transmission, manual or automatic.

And yes, as OWC says, engage the parking brake before putting a vehicle in Park or releasing the clutch on a manual.

semperfi1946

My 2021 Z51 comes on automatically sometimes. I was torquing wheel lug nuts to specs and the system activated about 2 minutes after I got out of the car. I also get some squeaking while backing out of garage and I need to tap brakes a few times to get rid of noise-really embarrassing with a car with only 1,900 miles on it.