SBC brake change

[Kam55]

Hi everyone

I was about to change my front brakes when I discovered that the SBC is under pressure and needs de-activating using scan tool.

Looks like Foxwell NT530 could do the job and much more (good investment) but I contacted their service team and they seem to be ''shut down''. I am not surprised given what's going on in the world.

Before I go to pay mechanic to do the job, does anyone in South Wales / Bristol area would be willing to lend me similar tool ? I could leave you deposit equal to the value of the device + fee for borrowing when I return it.

Don't seem to be any for sale right now second hand. I hope I am posting in the right forum area.

P.S. the car is 2005 CLS500 with SBC pump.

 

[bob6600]

I believe it can be deactivated without a diagnostic plugged in. There has been threads on this I'm sure. One thing I do remember is to put your keys out of range once the vehicle has shut down and do not open the door (which will wake the car up)

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

 

[Wearsthefoxhat]

You can disconnect the pump, the big plug on the side of the sbc unit.
I'm sure there is a thread on here regarding changing pads and discs with sbc.

 

[Kam55]

After all the reading and videos it all comes down to 1 question (cannot find definite answer to that):

- If I apply Mercedes official procedure (as per video above) to deactivate the pump, will that relief the pressure from the brake lines to caliper? I know that scantools do and show the actual pressure before and after.

Some materials out there suggest that this may not relief the pressure and I may damage the unit when pushing the caliper in. My pads are nearly gone ...

 

[OneForTheRoad]

I've done my brakes both ways, by taking both battery earths off and also locking up the car after jacking it up and removed the wheel wait for it to goto sleep. Both ways have let me push the pistons back with very little effort.

 

[E55BOF]

When the brakes are off, if you can spin the wheel by hand there's no pressure in the brake lines to the calipers. If there was, the brakes wouldn't be off.

 

[Kam55]

Thank you for the tips.

I seem to have no choice but to give it a go.


EDIT:

2 more questions:

Should the car be in Park or Neutral , when doing this job ? Once I lift it , I can't open doors/touch brakes till I do the key procedure through the window and spin the wheels.
One video, the wheels to be spun are drivers side. Since we are in UK, do we spin driver or passenger side?

 

[OneForTheRoad]

Park Locks up the gearbox not the wheels. Why the need to spin them , just change the pads , your over thinking it all.

 

[pmcgsmurf]

I always find it much easier (safer) to simply unplug the SBC system plug after getting the car into the service location if i don't have Star to hand.

Might be a cable tie to cut but easily replaced (or not).

 

[E55BOF]

Thank you for the tips. I seem to have no choice but to give it a go.

2 more questions:

Should the car be in Park or Neutral , when doing this job ? Once I lift it , I can't open doors/touch brakes till I do the key procedure through the window and spin the wheels.
One video, the wheels to be spun are drivers side. Since we are in UK, do we spin driver or passenger side?

I rather expect you can't take the key out of the ignition if it's not in Park.

 

[Kam55]

Hi everyone. It worked using the method from the video posted above. The pistons retracted easily by pushing the old pad against it.

It was tricky to raise the car on all 4 wheels but we managed. During the change , the alarm went off (someone drove by in a loud car) but I disarmed it with the key and all was well anyway.
The rear lights did not blink though, some suggest they should when SBC is activated again.

The nightmare was elsewhere - the punch out pins on the caliper did not want to come out easily. One was such a pain, it broke all the tools we had. Eventually it came out. The tools I bought were crap , I admit, but I could not find anything better available for collection same day.

I've already bedded the brakes in, changed front tires and did alignment (apparently only the front can be adjusted) and today is the first time I will go out for a proper drive !

A bolt was frozen on one of the drop links (I think that's what they called it) and when I first got the car after the alignment, the steering wheel massively off. It triggered the ESP malfunction right away. The garage fixed it , but said it was a pain in the #$# and I will need to change that suspension part next time. Not a shock given the car is 15 years old. They admired it otherwise