Brunty88

As the title says
I know how to use it but it appears to have suddenly stopped working.
Tried all types of things to activate but won't come on
Anyone else had this ?
If so solutions?
If not any ideas what it could be?
I tried replying in the other brake hold thread but was more about how to use it. So created this
Thanks
Rich

NotABaller

Jerry: disconnect the battery for 8 hours and try again.

manuelsm

happened to my 204 and it was the aux battery

Brunty88

Interesting
How did you find out that was the cause?
Where is it ?

Diabolis

I have yet to see one of them unicorn aux batteries on a W204 C63...

Brunty88

Back to the drawing board then

manuelsm

The dealer replaced the part and it started working again, that was in my 2013 c180 dont know if the 63 has one just wanted to help

zcct04

You might want to try the C-class forums for sedan and coupe. I'm not sure that all of them had this feature, but I'd guess a lot did, and there are a bunch more of them than AMGs. You'll want to do an advanced search and enter BRAKE HOLD
https://mbworld.org/forums/c-class-w204-83/
https://mbworld.org/forums/c-class-coupe-c204-156/

Diabolis

Does the hill start assist function work?

Brunty88

I think so
Race start still works how weird
I'll try the normal forum and see

Diabolis

Race start has nothing to do with it. Hill start assist uses the same components and circuits, so you need to check if the car is held stationary on an incline for the first second and a half after you let go of the brake. If the hill start assist works but the brake hold functionality doesn't, then I'm afraid the only way to diagnose it is with DAS Xentry.

Brunty88

Thanks I'll give that a try

Brunty88

right hill assist seems to work
on a hill hold brake on let go of brake car holds for a second or 2 then will start to roll forward

Diabolis

I think an MB service shop is your best bet at this stage.

Brunty88

Took to mb
Was a battery in a Sensor apparently