2003 R230 Sticky parking brake

[G7Wagen]

Had my SL55AMG since last summer... one job I need to look at is the parking brake is sticking which only began to happen after about 3 months after I bought her.... when I pull the release handle the foot pedal does not release.. and the brakes are on... a gentle lift of the foot pedal with my foot and they release completely... has anyone had the same issue? I left the car over winter with the brake off and in park so I can get it out of my small garage.

John

 

[Petrol Pete]

Does your car have one of these splitting the handbrake cable to the rear wheels ? It is a part used on many MB's (mine a 2006 C class) . On my car is it accessible from a bolted down hatch underneath the rear seat but you can see by the design that it is 'open' on the bottom side for access.

That is the main problem , crud gets thrown up from the road/driveshaft and it seizes up . I have just had mine replaced as the return spring snapped (same symptoms you encountered at the foot pedal) .

On my car the drive shaft & exhaust had to be disconnected and the petrol tank dropped (a bit) to get it out . Your car might have a slightly different set up but the clock spring in this adjuster cassette is the main one that helps return the foot pedal . The coiled spring on the pedal has no adjustment and taking it all apart to have a look is a royal pain in the a$$ (ask me how I know ) .

Whatever cable 'splitter' device your car has , that would be the first place to look . And if you can get to it give it a blast of lube.

 

[G7Wagen]

thanks for that... not looked under the car but i think it has aero panelling , I suspect there is a splitter under there somewhere semi seized

 

[slade1]

Push the pedal down hard it usually releases, if not hook it up with your foot.
Have been doing this for years in spite of proper maintenance, lubrication etc.

 

[Petrol Pete]

Like slade says ^^^ This can go on for years without a problem . But then one day - usually a few days before the MOT is due - the years of extra strain on the clock spring causes it to snap and the handbrake warning lamp and buzzer stay on continuously unless you drive with your foot hooked under the pedal .

Technically speaking the tester could fail the car if the pedal does not return under its own 'steam' but it's unlikely.

One of the problems related to this type of foot operated handbrake is lack of use - I almost never use mine when parked (in P) on the gravel outside my house, but use it you must just to keep it exercised for MOT time.

I wouldn't ignore it if I were you. Get it looked at.

 

[G7Wagen]

Mot is due in 3 weeks time... the pedal released without issue for the 4 months I was driving it after I bought it.... but just before I was due to put it away for winter.. it started sticking on... when released it stays off... My wife's 350coupe is nearly 12 years old and has never got stuck... Will be giving the SL a full going over a week or so before the MOT.. I can live without using the parking brake... but like most its nice to have everything working as it should..

 

[Petrol Pete]

If it gets through the MOT , then fine . But it is at the point where the pedal continuously drops (or does not return) and the buzzer stays on that the car becomes pretty much unbearable to drive , driving along holding the pedal up with your left foot for any length of time is no fun (ask me how I know !)

Just reaching under and disconnecting the switch is easier said than done. Let us know how you get on .

 

[G7Wagen]

I fixed my sticky parking brake issue (for now) I removed the cover of the lower dash after removing the 3 torx screws... unscrewed and removed the interior light attached to the panel.. and the diagnostic plug (2 smaller torx screws) the cable releases from the plastic mount of the port by sliding the block connector lock back about 25mm.. and it comes out.
Once the panel is removed, which can be fiddley getting it past the parking brake... you can see the parking brake cable clearly along with most of its mechanism....I sprayed it liberally with some WD40 along whist operating and releasing the foot brake mechanism... sprayed the upper pedal mechanism too...and operated it about 15 times.. (protect your carpet from oil drips as you do this. it now works without sticking . replaced the dash panel and its associated electrical bits... job done... tried it again today.. its fixed.. and operating and releasing properly.
All it cost was 15 mins of my time and a few squirts of WD40 (oil)
First pic is one of the dash removal method..(it shows LHD but RHD is the same) 3x torx screws under the dash, you can also my pic of under the dash of the torx screw and one of the diagnostic port screws. the other two pics show how the pedal system works.

 

[slade1]

WD40 is not a lubricant, the problem may return.
Will have a look at Haynes WS manual.

 

[slade1]

WD40 is not a lubricant, the problem may return.
Will have a look at Haynes WS manual.
Thanks for info

 

[Petrol Pete]

Item 92 on the schematic is where you really need to look to avoid further problems . As you know I have just replaced mine and I see yours is of a different design, but my recommendation would be to gain access to it and lubricate it .

 

[G7Wagen]

I have just looked at the oil I used and it is in fact lithium grease not WD40 same long thin application nozzle.. made by the same bunch.. similar can easy to mistake the two...

 

[G7Wagen]

Parking brake still working.. plus a 'no advisories' MOT pass.

 

[Neiltodd]

Sometimes just reversing a fraction after releasing the parking brake will unstick it.

 

[Petrol Pete]

Op is talking about pedal/cable sticking . Not shoes sticking to drums , but you are correct in using that method for freeing off the shoes.

 

[Mercedes-2010]

Like slade says ^^^ This can go on for years without a problem . But then one day - usually a few days before the MOT is due - the years of extra strain on the clock spring causes it to snap and the handbrake warning lamp and buzzer stay on continuously unless you drive with your foot hooked under the pedal .

Technically speaking the tester could fail the car if the pedal does not return under its own 'steam' but it's unlikely.

One of the problems related to this type of foot operated handbrake is lack of use - I almost never use mine when parked (in P) on the gravel outside my house, but use it you must just to keep it exercised for MOT time.

I wouldn't ignore it if I were you. Get it looked at.

Good advice...

 

[ALFAitalia]

WD40 is not a lubricant, the problem may return.
Will have a look at Haynes WS manual.
Thanks for info

According to the maker it is....from their FAQ page.

A QUESTION OF LUBRICATION​

Myth: WD-40 Multi-Use Product is not really a lubricant.

Fact: While the “W-D” in WD-40 stands for Water Displacement, WD-40 Multi-Use Product is a unique, special blend of lubricants. The product’s formulation also contains anti-corrosion agents and ingredients for penetration, water displacement and soil removal.