Parking brake light sticking on...HELP

jhonny

New Member
I have a C180 and when I release the parking brake by pulling the lever, the actual pedal and parking brake release ok, but the red parking light on the dashboard stays on and emits a warning every time i drive, when i move the parking brake pedal backwards, the red light on the dash goes out. Had it in to a mechanic and he has no idea. Does anyone know if this is an easy job to do, what part is required? Many Thanks
 

Micman

Senior Member
I'm no mechanic - but it sounds like the pedal sensor/switch isn't releasing fully so the dash warning light still thinks the pedal is down. Especially when you say the light goes out if you pull the pedal back up more yourself.

I've known of cases where cars brake pedals are released yet the rear brake lights stay lit up - this can be due to the pedal switch not releasing properly.

I'm sure someone will be along soon who knows more than me - and the correct technical terms for the parts!

:lol:
 

television

Always remembered RIP
The 202 has a spring on the adjustment parts under the cover under the rear seat. check that it is not broken. oil all this mechanism all up and make sure that it all swings and moves easily,, that should fix it
 

Cole@MBS

Forum Supporter
Authorised Forum Supporter
Sounds like a 203 to me guys, that will be the old linkage seized under the back seat, confirm its a 203???
 
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jhonny

New Member
I greatly appreciate all your comments. My car is a 2005 C180Kompressor. I dont think the problem will be under the back seat. Once i have released the foot pedal using the hand lever, it does release and the brake also releases, it is just the light that stays on. When i said that if i pull the parking brake pedal further back the light goes out, i am only pulling it back by around 1mm. I dont think this small movement would transfer back to parts under the back seat, however, I may very well be wrong. i just wasnt sure if i explained myself properly. Here's hoping the answer isnt far away and isnt too costly! Thanks again
 

bi-turbo

Senior Member
Nope not costly, is 95% of the time the linkage under the back seat as said previously, slightly slack cable not being pulled taught and retracting the pedal all the way off! simple fix.
 

Alex Crow

Senior Member
jhonny, hard though it may be to believe, the problem is all to do with adjustment, which is done under the back seat. if you apply the parking brake and count the clicks you will find that it goes down too far, perhaps 6 or more clicks. if adjusted correctly it will only travel 3 or 4 clicks, and when you release it the light will go out. try a forum search for the problem if you are still in doubt.
 

Wirral_guy

Active Senior Members
+1 for the above

I have recently adjusted mine as the slightest touch made the warning come on. Really easy to do and only needs a spanner (maybe a torx for the cover - can't quite remember)

Lift the back seats
undo the black cover (mine has 2 screws and a nut)
Underneath there is a 3 way cable junction swinging plate (not triangular but 1 in from the parking brake pedal, 2 out to the rear brakes - you'll know what I mean when you see it :))
adjust the cable coming from the front (tighten in small stages)
test the pedal, it should spring back to the top position gently rather than with a thump
adjust again if necessary until right
oil the links, cables, pivot point etc whilst you're there
replace cover

2 things to note:
Don't go too tight as this will leave the pads touching the drum when you next go for a drive :Oops:
Doing this on a CLK is a pain as you have to keep going in and out of the back via the driver's seat - should be a doddle in the C!

All in, it's less than 10-15 mins work.

HTH

Dave
 

wireman

Senior Member
I dont know about your model but on earlier cars with pedal parking brakes the switch is mounted on the pedal assembly, it looks just like an interior light door switch and is pressed to "off" by the pedal being in the fully raised position.
To see the assembly the panel above your left foot needs removal.
 
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jhonny

New Member
I would like to say a big Thank you to everyone for all your help. Problem is now fixed.
 

Richard Moakes

Senior Member
Been having similar problems on my R129.

Does anyone know if the cable from the pedal to the yoke should pull back taught to hold the pedal against the switch, or is it the friction of the pedal against the rubber damper ring that holds the pedal against the switch?

The brake is adjusted so that only 2 - 3 clicks is required, but watching the mechanism under the dash shows that the pedal releases when I pull the handle, makes contact with the switch but then bounces back and allows the switch to close again and cause the warning light to show?
 

television

Always remembered RIP
I think Richard that your cable is too tightly adjusted and those few clicks when you release it are not enough 6 to 8 is the normal,, there is a return spring I believe on your pedal you could check that or add one
 

raginbull

Member
+1 for the above

I have recently adjusted mine as the slightest touch made the warning come on. Really easy to do and only needs a spanner (maybe a torx for the cover - can't quite remember)

Lift the back seats
undo the black cover (mine has 2 screws and a nut)
Underneath there is a 3 way cable junction swinging plate (not triangular but 1 in from the parking brake pedal, 2 out to the rear brakes - you'll know what I mean when you see it :))
adjust the cable coming from the front (tighten in small stages)
test the pedal, it should spring back to the top position gently rather than with a thump
adjust again if necessary until right
oil the links, cables, pivot point etc whilst you're there
replace cover

2 things to note:
Don't go too tight as this will leave the pads touching the drum when you next go for a drive :Oops:
Doing this on a CLK is a pain as you have to keep going in and out of the back via the driver's seat - should be a doddle in the C!

All in, it's less than 10-15 mins work.

HTH

Dave
Hi Wirral_guy, I posted something earlier but not sure if it was sent as my internet crashed.
In short I used your instruction to adjust my parking brake to get the warning light off when released and ensuring the rear wheels still turned by hand when released. It worked ok for a week but now I find I have to put my toe under the pedal to get it to release fully.
Are there any shoes/pads specifically for the parking brake, and can these be adjusted?
 

na1191

New Member
Almost there

... adjust the cable coming from the front (tighten in small stages)
test the pedal, it should spring back to the top position gently rather than with a thump
adjust again if necessary until right ...

Dave

Can you please elaborate on how to tighten it (where from & using what). Thanks in advance :)
 

television

Always remembered RIP
Can you please elaborate on how to tighten it (where from & using what). Thanks in advance :)

Is your car a 202 or 203 please, there is an panel that comes off under the rear seat squab where you can adjust the cable.

This is the 202 layout and almost the same as the 203



The correct way is to back the cable off, then go to each wheel and adjust the parking brake shoes so that the wheel locks, then back off about 6 clicks or so till the wheel turns with just a gentle rubbing.

When both wheels are done you go back to the parking brake cable under the eat and adjust the cable so the about 8 clicks lock the wheels
 

whitenemesis

Senior Member
The number of clicks through which the pedal should travel depends on whether the pedal assembly has a pushed notch or the pulled notch.

Pushed notch should be 5 clicks
Pulled notch should be 1 click
 

na1191

New Member
The correct way is to back the cable off, then go to each wheel and adjust the parking brake shoes so that the wheel locks, then back off about 6 clicks or so till the wheel turns with just a gentle rubbing.

When both wheels are done you go back to the parking brake cable under the eat and adjust the cable so the about 8 clicks lock the wheels

Thank you for such a quick response, joining this forum was a great idea.

So it looks just like the diagram but with both looking similar I'm not 100% certain. How can I tell the difference between a 202 & a 203?

Additionally I did remove the panel however, due to the lack of my mechanical knowledge, I'm unsure what and more precisely how to do the next step; e.g. back the cable off? how does one adjust the parking break shoe? etc.

If you feel my lack of knowledge/skill is too great to carry out the task please do let me know so that I can give into the garage. BTW, would anyone know how much this should set me back at Mercedes & a normal garage.
 
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