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Park Brake Pedal Doesn't Return

19K views 18 replies 8 participants last post by  Gotglasses 
#1 ·
The parking brake works fine, except the pedal doesn't come up all the way by itself. It needs to be pulled up the last few inches so the light turns off.

Has anyone experienced this problem? Is there an adjustment or possibly a return spring that might be broken?
 
#9 · (Edited)
I never got around to doing anything about the parking brake. However, the parking brake stopped working completely so I finally had no choice. The parking brake release stuck in the pulled out position so the brake would not hold at all. I removed the parking brake pedal and found that the end of the clock spring popped out of the hole it's supposed to be in. No idea why or how that happened. I put it back into place, replaced the parking brake pedal and it's working again, at least sort of working. The pedal is still slow to return.

Does anyone know why MB changed the design of the parking brake pedal? My ML has the old design. See image below to tell the difference.

Also, it was relatively easy to remove the cable from the pedal, but it was a b*tch to replace it. It's not obvious at all how to use the "slack adjuster". I did notice that there is a spring at the back end of the slack adjuster that is somewhat rusty. Does it have anything to do with the pedal not returning?

 
#19 ·
Same Parking Brake issue - SL500 W230

I never got around to doing anything about the parking brake. However, the parking brake stopped working completely so I finally had no choice. The parking brake release stuck in the pulled out position so the brake would not hold at all. I removed the parking brake pedal and found that the end of the clock spring popped out of the hole it's supposed to be in. No idea why or how that happened. I put it back into place, replaced the parking brake pedal and it's working again, at least sort of working. The pedal is still slow to return.

Does anyone know why MB changed the design of the parking brake pedal? My ML has the old design.

Also, it was relatively easy to remove the cable from the pedal, but it was a b*tch to replace it. It's not obvious at all how to use the "slack adjuster". I did notice that there is a spring at the back end of the slack adjuster that is somewhat rusty. Does it have anything to do with the pedal not returning?
I had the exact same issue in my 2004 SL500 , attached is a picture of the problem. Perhaps someone yanked it out so hard that they popped out the brake drum spring arm? Either way in photo you can see the worn spot on the swinging release cam and the return spring extended. The emergency brake will stop car fine, but it will not latch into place and release handle can fall out off the cable. After popping the thick spring arm back into the cam brake pedal clicks and holds . The teeth on the brake pedal do nothing but make the clicking noise, they do not hold anything. The big spring closes on a brake drum and holds the pedal down. Mercedes engineering!

Re the slack adjuster - you could try to take it up a couple of notches, it is under the exhaust pipes in my car and the exhaust system has to be removed to adjust the cable!!! I find that if I set the brake firmly it has plenty of "pop" on the release.
 
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