R230 Handbrake not fully releasing

[Ronnie]

Well it would wouldn't it .

I'll word it differently for the infidels.

Try putting the car into drive on a flat road and see if the car will move off in drive with little revs or does it hold and creak , even doing this won't be conclusive as your rear caliper could be sticking. Get it up in the air and spin the wheels ,as per instructions. Remove the rear pads, if the wheel still won't turn then yes it's handbrake related.

It does still “crawl” when in drive and no acceleration applied

 

[OneForTheRoad]

It does still “crawl” when in drive and no acceleration applied

Even with the handbrake on ?

 

[Ronnie]

Even with the handbrake on ?

Haven’t tested it with the handbrake on…will try that later today and revert

 

[OneForTheRoad]

Haven’t tested it with the handbrake on…will try that later today and revert

 

[Ronnie]

Even with the handbrake on ?

No definitely doesn’t ““crawl” when the brakes are applied

 

[OneForTheRoad]

No definitely doesn’t ““crawl” when the brakes are applied

Seems to point to the handbrake is applying and releasing then . Possibly/ maybe not 100% fully , get it into another garage for a brake check , caliper/pads/discs and handbrake shoes.

 

[Petrol Pete]

Here is the foot pedal , the red arrows are from a different thread showing the release cable ,2a & 2b are the plastic bits that make the 'clicking' noise and are not related to what we are discussing here , but you will note there is no adjustment here and the worst thing that usually happens here is the spring pop's out of the clip to the left of the lower arrow. You will know when this happens as the red light will not go out on the dash as the pedal will not return all the way up to make the switch.

Basically don't waste your time poking around here.

 

[Petrol Pete]

From experience, do NOT start just poking around hoping all will be well and beware of garages who don't know (or do know) how this system works.

Once you start taking it apart there is no going back (see my post #12) You have a few choices depending on how handy you are with the tools.

Here are a few suggestions.

As we said , rear wheels in the air , see how they spin.

Remove roadwheels and try to adjust shoes through the small hole in the hub.

Remove callipers and discs exposing the shoes hoping they don't look like mine in post #12

All the parts are widely available , the whole shoe/spring/adjuster kit can be bought as one , stone/dust shields either MB or aftermarket , same for discs . Splitter only from MB.

I used to think dragging the parking brake while driving slowly would 'clean it up a bit' but since I have had a close look at how it has been designed I would strongly recommend NOT doing that.

 

[Ronnie]

View attachment 160427

Here is the foot pedal , the red arrows are from a different thread showing the release cable ,2a & 2b are the plastic bits that make the 'clicking' noise and are not related to what we are discussing here , but you will note there is no adjustment here and the worst thing that usually happens here is the spring pop's out of the clip to the left of the lower arrow. You will know when this happens as the red light will not go out on the dash as the pedal will not return all the way up to make the switch.

Basically don't waste your time poking around here.

Thanks for that advice.
The brake pedal appears to come right back up.
However when “releasing” the ha brake there is no sound or physical feel of the handbrake
actually releasing, if that makes sense

 

[Ronnie]

Well it would wouldn't it .

I'll word it differently for the infidels.

Try putting the car into drive on a flat road and see if the car will move off in drive with little revs or does it hold and creak , even doing this won't be conclusive as your rear caliper could be sticking. Get it up in the air and spin the wheels ,as per instructions. Remove the rear pads, if the wheel still won't turn then yes it's handbrake related.

Took the car out for short run…tried the handbrake/accelerator and the handbrake held fast..
However, this is going to “muddy the waters”
I noticed the brakes
We’re a little “spongie” so pumped the brake pedal a few times and the error message “SBC Unavailable” appeared
From my limited knowledge this points away from the handbrake being the problem after all..

 

[OneForTheRoad]

Took the car out for short run…tried the handbrake/accelerator and the handbrake held fast..
However, this is going to “muddy the waters”
I noticed the brakes
We’re a little “spongie” so pumped the brake pedal a few times and the error message “SBC Unavailable” appeared
From my limited knowledge this points away from the handbrake being the problem after all..

Could just be SBC hold that wasn't working. ?? It requires certain conditions to be met. Some models it was deleted from the ECU , it never worked on my 2004 e320 .

SBC brake systems I'd say were the best ever tbh. But stupidly expensive and technical if they ever fail.

If your original issue ,which was hot discs . Then I'd suggest seeing about rear caliper servicing .

SBC brakes don't use a conventional vacuum servo , no amount of brake presses will alter brake pedal pressure, simply because under the pedal is only a simple switch . On and off .

 

[Ronnie]

Could just be SBC hold that wasn't working. ?? It requires certain conditions to be met. Some models it was deleted from the ECU , it never worked on my 2004 e320 .

SBC brake systems I'd say were the best ever tbh. But stupidly expensive and technical if they ever fail.

If your original issue ,which was hot discs . Then I'd suggest seeing about rear caliper servicing .

SBC brakes don't use a conventional vacuum servo , no amount of brake presses will alter brake pedal pressure, simply because under the pedal is only a simple switch . On and off .

So would you say the problem is not handbrake related ?

 

[OneForTheRoad]

So would you say the problem is not handbrake related ?

Going back to original problem of wheels getting hot , there's only 2 things that would cause friction/heat . Which I've mentioned already .

 

[Petrol Pete]

We are back to getting the rear wheels in the air. Pop a trolley jack under the rear differential , lift the car a bit and see if the wheels can be spun by hand with the parking brake off.

If so your problem lies elsewhere.

 

[Ronnie]

Différent garage determined discs need replacing..
Had new discs and pads fitted all round..
Took it for 15 mile run mostly motorway so little
use of the footbrakes..
Rear wheels both getting a bit of heat in them, the O/S more than the N/N and not nearly as hot as previously…
Will take it back the garage tomorrow for check over but the problem definitely not fully resolved

 

[OneForTheRoad]

Différent garage determined discs need replacing..
Had new discs and pads fitted all round..
Took it for 15 mile run mostly motorway so little
use of the footbrakes..
Rear wheels both getting a bit of heat in them, the O/S more than the N/N and not nearly as hot as previously…
Will take it back the garage tomorrow for check over but the problem definitely not fully resolved

If they simply replaced the discs but didn't refresh the calipers ,then the discs will fail in no time , if the caliper is sticking ....

 

[Ronnie]

If they simply replaced the discs but didn't refresh the calipers ,then the discs will fail in no time , if the caliper is sticking ....

When you say “refresh” do you mean replace ?
They said they checked the calipers and they were OK

 

[OneForTheRoad]

When you say “refresh” do you mean replace ?
They said they checked the calipers and they were OK

No , just a check for sticky slide pins and sticky piston. Re your heat issue , even some light braking will cause your discs to heat up . Sticky calipers and binding brakes make the discs radiate heat you can feel and smell .

 

[ToeKnee]

When they replaced the discs, did they overhaul the inner handbrake mechanism too?

 

[Petrol Pete]

As post #39

What dis they do to the handbrake shoes and mechanism ? Is their any mention of them on the invoice ?

The handbrake , after all , is what started this thread.