Replacement park brake mechanism

[Funkyboy]

Hi All,

Been quoted £320 to replace the footbrake parking mechanism on my 14 plate E250. Symptoms are parking brake pedal will rachet down but comes straight back up and release handle is now just loose.
Does this price sound about right?
Thanks

 

[keith of kent]

My 2015 E class sometimes suffers from the parking brake not releasing easily. When this happens I give the mechanism by the pedal a good dose of silicone spray.
Not saying that would solve your problem but I would give it a go

 

[Stratman]

If you are even remotely handy with screwdriver and pliers (if you can change a fuse you can do this), remove the panels above your shins and stick your head under there. There's a very high chance 'Spring' has popped out of its slot in 'Plastic lever'.



Put it back with your pliers and while you're under there make sure 'Release spring' hasn't come adrift.

 

[Funkyboy]

If you are even remotely handy with screwdriver and pliers (if you can change a fuse you can do this), remove the panels above your shins and stick your head under there. There's a very high chance 'Spring' has popped out of its slot in 'Plastic lever'.

View attachment 150253

Put it back with your pliers and while you're under there make sure 'Release spring' hasn't come adrift.

Thanks I will have a go at this. Are the panels straight forward to remove?

 

[Stratman]

Just about. You'll need a T20 (torx) screwdriver, although if you don't have one a suitable flat bladed one will work. The panels may have ventilation ducts moulded into them so be careful when replacing them. There'll also be a load of foam sound insulation in there. I never worked out how it all went back.

 

[Funkyboy]

If you are even remotely handy with screwdriver and pliers (if you can change a fuse you can do this), remove the panels above your shins and stick your head under there. There's a very high chance 'Spring' has popped out of its slot in 'Plastic lever'.

View attachment 150253

Put it back with your pliers and while you're under there make sure 'Release spring' hasn't come adrift.

When you say spring

Just about. You'll need a T20 (torx) screwdriver, although if you don't have one a suitable flat bladed one will work. The panels may have ventilation ducts moulded into them so be careful when replacing them. There'll also be a load of foam sound insulation in there. I never worked out how it all went back.

Thanks I've got torx so will have a go

 

[Stratman]

'Spring' is the big coil spring wound around the cylinder at the top of the foot pedal. It's the one that returns the pedal when you pull the lever. Sometimes the end you can see in the picture comes out of its slot in the black plastic release lever. I put a slight bend in it before putting it back in place, to give it a better chance of staying put. The release handle goes floppy because the black plastic lever can get stuck in the up position, removing all tension from the cable. The small release spring, whose function is to return the handle to its rest position can get pulled out so make sure it's okay.

 

[OneForTheRoad]

Look on YouTube, there's videos all about this very topic.

 

[fifermerc]

I was amused by the way you say “stick your head in there”, having removed the panel above the pedals. You must be a circus contortionist ?
I’ve had this happen on my E350 before, and as (bad) luck would have it, the same thing happened a couple of days ago. I took the panel off this afternoon - as you say, it needs care, as there are a few cables attached - but before I could “stick my head in”, it started raining, so it’ll need to wait.
Good post though. Getting the panel off isn’t too bad, getting your head in there to see what’s happened, and then getting hands and tools in to sort it, not quite so easy. I’m just hoping that in my case it’s the spring that’s popped again and nothing broken that needs replaced.

 

[Stratman]

I'm not the largest of people but I still ended up lying on my back with my head in the footwell and my feet over the seat back. I didn't want to put the OP off!

 

[RichardF]

I'm not the largest of people but I still ended up lying on my back with my head in the footwell and my feet over the seat back. I didn't want to put the OP off!

Ouch, not looking forward to this, are chiropractors more or less expensive than mechanics?

 

[Funkyboy]

If you are even remotely handy with screwdriver and pliers (if you can change a fuse you can do this), remove the panels above your shins and stick your head under there. There's a very high chance 'Spring' has popped out of its slot in 'Plastic lever'.

View attachment 150253

Put it back with your pliers and while you're under there make sure 'Release spring' hasn't come adrift.

If you are even remotely handy with screwdriver and pliers (if you can change a fuse you can do this), remove the panels above your shins and stick your head under there. There's a very high chance 'Spring' has popped out of its slot in 'Plastic lever'.

View attachment 150253

Put it back with your pliers and while you're under there make sure 'Release spring' hasn't come adrift.

I've taken a picture of my parking mechanism does this spring look in the correct place?

 

[Stratman]

I've taken a picture of my parking mechanism does this spring look in the correct place?

No. Look closely to the left of very end the spring, you can see the gouge mark it's made on the black plastic part as it came out. It should be in the large teardrop shaped hole immediately up and left of its current location. See my picture in post number 3.
If you can, bending a slight curve in the spring (towards the black plastic lever) will help prevent it jumping out again.

 

[Funkyboy]

No. Look closely to the left of very end the spring, you can see the gouge mark it's made on the black plastic part as it came out. It should be in the large teardrop shaped hole immediately up and left of its current location. See my picture in post number 3.
If you can, bending a slight curve in the spring (towards the black plastic lever) will help prevent it jumping out again.

Stratman thank you so much for your help all working again now.
I was quoted £360 by a mercedes independent specialist who even tested it. They must have known it could have been something as simple as this.
Thanks again

 

[Funkyboy]

No. Look closely to the left of very end the spring, you can see the gouge mark it's made on the black plastic part as it came out. It should be in the large teardrop shaped hole immediately up and left of its current location. See my picture in post number 3.
If you can, bending a slight curve in the spring (towards the black plastic lever) will help prevent it jumping out again.

Hi Stratman
Can you explain what way to bend the spring to stop it coming out again please. On the pictures do you mean bend it further up or to the left or right?
Thanks

 

[Stratman]

I bent it towards the plastic lever, just a little curve to help it stay in the slot. It wasn't much, a millimetre or two at most.

 

[CMJohn]

In my experience, you can fix the spring yourself like this, but it will only be a matter of time before it pops out again. Definitely worth a try, but I ended up needing to attend to it every few weeks. Bending the spring helps if you can, but the cause of the problem is worn parts that need replacing, and yes £320 sounds OK if that's what they're doing.

 

[CMJohn]

A symptom that preceded this happening was the foot pedal becoming stiff at times, needing a toe under it to pull it back. If this is happening, there is a chance the brake cables may need replacing, as the cause can be corrosion/lack of lubrication inside the plastic sleeves. This would be anothet few hundred quid on top.