We have my dads car and the brakes are squeaking and i am 99% sure its just the piston rubbing on the pad backing plate as its quite a common fault on this car (merc B180). Is it possible just to remove the pads from the caliper with the caliper in situ like i can with say my shimano pads. I am hoping that after removing the retaining clip and possibly a pad wear sensor wire then i will just be able to pull them out and smear with copper grease and refit, pretty much a 15 minute job? Hoping that i dont need to remove caliper and rewind pistons back in.

Loads of dust can cause squeekage, try a good clenout with a hose…

Failing this check YouTube, loads of helpful films on there

Obviously I’ve no idea how technical you are but for what is a £40 ish job at a small garage, and the chance of ether making a mess of it of at worst causing a brake failure is it worth the bother, yes it’s a quick and easy job but so is most things when you know how to do them!!!

Generally speaking, it’s not the same as doing it on a bike. You will usually have to remove part of the caliper. Which is just a couple of bolts, but on cars, where these things are subject to quite a lot of heat, they can be quite stubborn.

It’s not a ball ache of a job. But as an absolute novice, you might well spend 2 or 3 hours doing it. (possibly more if you have issues).

How old are the pads? For the price of them, I’d probably change them if I was going to have them out. Unless they’re relatively new.

I wouldn’t discourage doing it mind. I think it’s good to work on your own cars. And as experienced as they are, a time-pressed mechanic is likely to do the bare minimum. If a job’s worth doing…

I am pretty handy with the tools so fairly confident of doing it i just dont want to run in to something that either requires specialist tools or a computer reset of some description. I think there is some sort of pad carrier that might need to come out to gain access to the pads. I cant find anything on youtube specific to the B180 so looking at a few generic ones might help i guess.

For me, it would be worth £10 to have the full instructions.

http://www.emanualonline.com/Cars/Mercedes/Mercedes-B_Class-Workshop-Manual.html

As said, not difficult but check the tools you’ll need first.
Usually std stuff but Ford (I think) needed a 7mn hex drive once, & torx isn’t unusual.
For what’s effectively a service item it’s likely to be a 13mm socket. Bolts out, calliper off (with pursuasion…), then pads just lift off. If there’s a pad retaining spring, take a photo before you release it.

Have you taken the wheel off to have a look?

Depends. Unlikely if it is the single floating piston calliper or if an AMG model where you will most likely have to remove the calliper. If it has the 4-piston type of calliper then the pads tend to slide out the top like an MTB calliper. However even then it is often best to remove the calliper because you need to back the callipers off from the disc and that is difficult to do if you’re not removing the calliper if you want to retain the pads. Anyway removing the calliper is a quick an easy job – 2 bolts per calliper and it will then enable you to give the pistons a good clean.

Often car pistons need to be ‘wound’ in/out as opposed to bikes which can just be pushed/levered.

And when you jack up the car and take the wheel off, either use axle stands as well or push the wheel under the sill – just in case…