Parking brake reset
Thread Starter
Junior Member
Joined: Apr 2022
Posts: 36
Likes: 11
From: michigan
S550
Parking brake reset
I have a 2008 S550. A scraping noise led to discovery a right side shoe was loose where a spring holds it to the backing plate. The spring was not attached because the backing plate rusted where the spring attached. A replacement backing plate is non existant (new or salvage). Because I never use my parking brake the mechanic removed shoes, springs and all hardware. He cautioned me not to engage the parking brake. Scraping noise was gone and I didn't use the parking brake. Problem solved for a year.
Last week an alignment was done after suspension work. The alignment tech unkowingly put on the parking brake. I now get the dash message and blinking "Park". The message can be reset with the steering wheel button but blinking PARK stays. It doesn't affect driving but is annoying. I searched for a shop with the right scanner to reset it but it could not be reset. I pulled the safety release cable in the fuel filler area . It comes out a few inches but it didn't do anything. Apparently the motor that pulls the brake cable does not sense tension/resistance of shoes against the drum (because there are no shoes). This makes the module think there is a problem and causes the message a.d blink. Is there a way to turn off the indicator without taking everthing apart?
Last week an alignment was done after suspension work. The alignment tech unkowingly put on the parking brake. I now get the dash message and blinking "Park". The message can be reset with the steering wheel button but blinking PARK stays. It doesn't affect driving but is annoying. I searched for a shop with the right scanner to reset it but it could not be reset. I pulled the safety release cable in the fuel filler area . It comes out a few inches but it didn't do anything. Apparently the motor that pulls the brake cable does not sense tension/resistance of shoes against the drum (because there are no shoes). This makes the module think there is a problem and causes the message a.d blink. Is there a way to turn off the indicator without taking everthing apart?
MBWorld Fanatic!
Joined: Aug 2014
Posts: 5,322
Likes: 1,678
S500
I don't think that part could be unobtainium - is it part 120 - if it were just weld up the broken bit - that bit for other models is all over the internet including the older w220
https://nemigaparts.com/cat_spares/e...71/63v/42/045/
https://nemigaparts.com/cat_spares/e...71/63v/42/045/
Super Member
Joined: Oct 2023
Posts: 569
Likes: 197
W221 S500
If there's a fuse for it, pulling it might help.
Failing that refit the hardware. Even a penny washer and JBWeld would fix the back plate permanently. Even a backplate from a base W204 would get the job done although you may have to remove the outer lip from the plate to clear the larger discs.
Mercedes mechanical rear parking brake hardware was pretty much unchanged across the board from the last Millennium until 2014 is when they went to the more stupid electronic caliper actuation.
Incidentally, if you saw the size of the parking pawl in the gearbox, you would immediately get your parking brake serviced and working properly. It won't take much force on an incline to snap it then it good bye car. Notwithstanding the total lack of E brake should you actually need one. And as a school bus driver, you of all people shouldn't need reminding about the responsibility that goes with operating a vehicle.
Rant over, but get it fixed.
Failing that refit the hardware. Even a penny washer and JBWeld would fix the back plate permanently. Even a backplate from a base W204 would get the job done although you may have to remove the outer lip from the plate to clear the larger discs.
Mercedes mechanical rear parking brake hardware was pretty much unchanged across the board from the last Millennium until 2014 is when they went to the more stupid electronic caliper actuation.
Incidentally, if you saw the size of the parking pawl in the gearbox, you would immediately get your parking brake serviced and working properly. It won't take much force on an incline to snap it then it good bye car. Notwithstanding the total lack of E brake should you actually need one. And as a school bus driver, you of all people shouldn't need reminding about the responsibility that goes with operating a vehicle.
Rant over, but get it fixed.
Last edited by AL5461; Sep 13, 2025 at 01:07 PM.
Super Member
Joined: Jun 2025
Posts: 784
Likes: 249
From: USA
The module detects the missing shoes as a fault. You have two options: reinstall the parking brake hardware, or find a specialist with advanced Mercedes coding tools to disable the entire EPB module. A basic scanner cannot fix this. The warning will stay on otherwise.
