Can't get the rear brake piston to compress! 2016 CX-5

...and people talked trash about me paying the dealer $150 to do my brakes...

Seriously, you're doing it old-school, man. I did what you are doing a decade and a half ago, and it worked fine on the cars then. These new cars? They are annoying in that all of them work different, and are a PITA to learn about, especially if you break something $$ in the learning. I can empathize with OP, this is how my brake job on my Infiniti went. Since then...dealer.
I guess you didn't get the memo...technology is supposed to make life easier..
 
I guess you didn't get the memo...technology is supposed to make life easier..
Supposed to ⋯ ;)

Unobtanium is right on something. Many years ago I took apart a Borg Warner automatic transmission from a '72 Ford Capri without too much hesitation. Everything was mechanical, what you see is what you get. Nowadays everything is computerized and sophisticated sometimes proprietary equipment is needed to diagnose the problem. Yeah it's a totally different era.
 
So by replacing the rear disk pads, the EPB motor power needs to be disconnected after its been put in the maintenance mode. And the rear caliper needs to be removed to take the pads out. Dont know why but its the perfect time to lub the caliper pins. Never rotate the caliper piston while pushing it into the caliper with those special brake tool or the caliper internal parts could be damaged! The only brake tool you might need is a traditional disk brake expander tool showing in the picture. A large C clamp should do the job too.

Okay....Dammit. At least now I know you merely need to push it back. Fortunately my kit should still allow me to do that. Thanks for the clarification.
 
Okay....Dammit. At least now I know you merely need to push it back. Fortunately my kit should still allow me to do that. Thanks for the clarification.
The fancy brake tool set definitely is an overkill to 2016 CX-5s rear brake job. I have a set too and used only once for my VW Passat.
 
Success! Was able to get back at it today. I had to take the EPB motor off the right rear caliper and turn it down and used the compression tool (got one at Walmart for $8 that worked well). I could not get it flush with the caliper for some reason though, and I'm worried that there might have been something wrong with that caliper. I'll have to keep an eye on it. At any rate I was able to get it compressed just enough to easily fit over the new pads, then I went the other side and it went without a hitch. Compressed all the way down and easily fit over the pads. Once it was all done I was able to turn off the maintenance mode with no problem and took it for a ride to make sure everything was ok. I think i'm good for now. Going to do the fronts this weekend probably even though they're good enough to pass inspection. Hate doing car work in the winter.

Thanks for all the replies!
 
i used aftermarket pads from AutoZone (WearEver brand) and put new rotors on (also Autozone, painted with 2 year warranty). My car is a grocery getter, not a race car so i don't spend money on racing parts. Never had any problem with aftermarkets. Had more problems with OEM than aftermarket to be honest. I got my brake expander tool at walmart. Cheap ($8) but it worked just fine.
 
i used aftermarket pads from AutoZone (WearEver brand) and put new rotors on (also Autozone, painted with 2 year warranty). My car is a grocery getter, not a race car so i don't spend money on racing parts. Never had any problem with aftermarkets. Had more problems with OEM than aftermarket to be honest. I got my brake expander tool at walmart. Cheap ($8) but it worked just fine.
So have you even had newly revised rear calipers replacing your old ones based on the TSB I mentioned earlier?
 
I've never had my calipers replaced. Never had any symptoms that I noticed. Probably because I almost never used the EPB. Car is out of warranty now with 48k miles.
 
I've never had my calipers replaced. Never had any symptoms that I noticed. Probably because I almost never used the EPB. Car is out of warranty now with 48k miles.
The easiest way to tell if your rear calipers are having problem is to compare the inner and outer disk pads on each side. If they are wearing at different speed, i.e. the outer one of your old pad is thinner than the inner one, this usually means your rear calipers have problem on EPB. But since you hardly use the EPB, you may not be able to see the difference.
 
the inner was pretty thin and the outer still had about 3/16 or so on it if i remember right. i didn't think that was out of the ordinary from what i've seen before on brake pads. the way the rotors were scored i was surprised i never heard any squeal out of them.
 
the inner was pretty thin and the outer still had about 3/16 or so on it if i remember right. i didn't think that was out of the ordinary from what i've seen before on brake pads. the way the rotors were scored i was surprised i never heard any squeal out of them.
Diffetent thickness of old pads can also be an evidence of faulty caliper due to insufficient accuracy of the screw threads on EPB even if you didnt hear any squealing noise.

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^Thanks.

I did not have those symptoms and pads seemed to wear evenly. I guess the whitened color indicates a caliper is dragging the pads.
 
hey guys, I just saw this on Pinterest and thought I'd pass it along. Seems like a pretty solid idea. Haven't tried it though. BTW, I did my front brake pads today and it was easy-peasy. took me about a half hour to do both sides. So look at this piston compression tool. You might even have one already. looks like you have to saw off part of the caulking gun.

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Good grief, I*ve just come across this and seen the trail of devastation for what should be a simple job. I keep reading that you need a piston wind back tool - no you don*t. You only need that if you have the old manual handbrake. If you have the electric (EPB) you must not attempt to wind it back and if you follow the instructions to the letter it is so easy and on return, they are self adjusting. You must not operate maintenance mode with the pads removed as seen. I can*t imagine the logic but I suppose if it isn*t fully understood you can get in trouble. They added the precaution of disconnecting the wire only to stop getting muddled about where the calipers are.
 
Sorry to revive a dead thread.

Hi everyone, looking for some help on the same issue here. I messed up in the same way and I've got the motors off for the electronic parking brakes but the pistons are all the way out and I can't get them in much at all.

When I turn the screw the EPB clockwise the piston does retract slightly then stops as the screw tightens and the whole piston starts to turn. The opposite happens counter-clockwise and the piston comes out slightly and the screw tightens and the whole piston turns. I've tried getting the piston to compress with a c-clamp in various positions of the screw and it just won't go any further (it's very far out similar to OP's first post).

If it's out too far, anything else to get it back in?
 
Turn screw clockwise, use clamp to press the piston, and repeat

Or

Get a set of the brake tools and turn the piston in

Or

If possible, put everything back together, enable maintenance mode, press the piston in
 
Turn screw clockwise, use clamp to press the piston, and repeat

Or

Get a set of the brake tools and turn the piston in

Or

If possible, put everything back together, enable maintenance mode, press the piston in

Thanks for the reply. I think the only viable option is #1. The piston came out so far I can't get a caliper tool in to turn the piston as you've stated in #2 and in any case, don't these ones go straight back in? For option 3, if I put the motor back on there is nothing rigid enough to clamp to try and push the piston back in (the housing is plastic and would deform and the regular tool won't fit with the caliper so far out).

For method #1, do you turn the screw, push with a clamp and turn more? I've tried this a lot already and there reaches a point I can't turn the screw any further because it's trying to turn the whole piston head (which is clamped). If I take the clamp off I can then turn the screw further clockwise but the whole piston head is just turning and not winding back in. If I try and turn it counter-clockwise the piston will come OUT a little bit and then tighten down and then also turn the whole piston.
 
Maybe try this.. I assume you have released the epb prior to removing the motor off of the caliper

If so, mount the motor on and activate maintenance mode. Hopefully this will rotate and loosen the screw so you can press the piston back with a basic depressing tool. But just in case, put something in between the pads to prevent piston from coming out in the event you did the opposite when enabling maintenance mode

Edit
Actual maybe even do this...
Run to your local auto part store and get a $10 spreader tool to put pressure on the inner pad against the piston. Make sure the two raised dots on the back of the pad are locked into the groove of the piston. That way the piston will be stationery while the screw turn.
 
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Maybe try this.. I assume you have released the epb prior to removing the motor off of the caliper

If so, mount the motor on and activate maintenance mode. Hopefully this will rotate and loosen the screw so you can press the piston back with a basic depressing tool. But just in case, put something in between the pads to prevent piston from coming out in the event you did the opposite when enabling maintenance mode

Edit
Actual maybe even do this...
Run to your local auto part store and get a $10 spreader tool to put pressure on the inner pad against the piston. Make sure the two raised dots on the back of the pad are locked into the groove of the piston. That way the piston will be stationery while the screw turn.

I haven't tried using the EPB motor to do it but I did try to use the old brake pad in there when I turned the screw so the piston could not rotate but again, after a certain point the screw tightens down and will not budge. I assume I can put more torque on it than the EPB motor can. I was trying to compress as I turned the screw so I wonder if it's getting bound on something.

I'm not sure how the mechanism works inside but I feel as though it's not something that's easy to "wind back" with the screw.
 
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although it's for cx-9 but I'm confident it's similar if not the same.

But it seems like you've tried many times and still couldn't compress, I'm kinda stumped for ideas. Hopefully others might be able to give some insight.

By the way are you having trouble with both calipers or just one side?
 
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