Guide Maintenance Mode for 2016 / 2017 CX-5 electronic brakes

Questions ~~!! Please Help~!
I own a used car, and just start chaning the brake the first time in my hand for this car.
I saw the rear piston plastic ring twisted. Does it mean it was previously pushed back by rotating the piston ? Or the piston will twist in its normally usage but for some reason the plastic part doesn't twist the same time as the piston twist and ending twisted plastic ring?
I want to fix it but not sure if it's ok to twist the piston for the purpose.

Another question, I know the piston should align with the little knot on the brake pad. Doesn't it mean the piston normally can't rotate when applying brake? If it's the case, why it need to be design in a way there seems a way to rotate it, while we shouldn't?

Sorry for so many questions. But I am curious about why it shouldn't be rotate and how the rotation actually work for this brake.
 
Questions ~~!! Please Help~!
I own a used car, and just start chaning the brake the first time in my hand for this car.
I saw the rear piston plastic ring twisted. Does it mean it was previously pushed back by rotating the piston ? Or the piston will twist in its normally usage but for some reason the plastic part doesn't twist the same time as the piston twist and ending twisted plastic ring?


"plastic ring" ? do you mean the dust boot around the grooved piston ? this is a picture I got off the internet, it's not the CX-5
but you get the idea
1681527d1506945506-diy-honda-civic-brake-overhaul-pistons-caliper-lubrication-rear-piston.jpg

I assume you are refering to the rubber seal (also called dust boot) around the piston. If your's is twisted, the previous owner may have rotated the piston instead of using the maintenance mode to push it straight back, it's best to try to "untwist it" since it may be stretched and causing too much stress that it may rip as the piston gets extended


I want to fix it but not sure if it's ok to twist the piston for the purpose.
you can try to un-twist it if you unbolt the caliper assembly and press on the brake pedal to extend the piston out so it's easier to straighten out the dust boot, use a flexible plastic spatula so to work the dust boot back to normal, use the plastic spatula https://tintdepot.com/product/shank/ and be careful not to cut or rip the dust boot rubber OR I think you solution might be better, engage maintenance mode and that will back off the motor and you can rotate the pistion back and "untwist" the boot, this is actually in the manual that once you engage the maintanence mode, you're allowed to rotate the piston. what year is your CX-5 ? only 2016-2019 have maintenance mode.

Another question, I know the piston should align with the little knot on the brake pad. Doesn't it mean the piston normally can't rotate when applying brake? If it's the case, why it need to be design in a way there seems a way to rotate it, while we shouldn't?

I believe it doesn't rotate if coming out, and you don't rotate to get it back in, you need to engage maintenance mode to back off the motor, once it back off the piston can go back and forth straight, you do not rotate, you only rotate very little to make sure the groove lines up with the pin on the back of the brake pad. If you don;t line it just right , you will hear a loud clanking sound every time you break, see my post #22, https://www.mazdas247.com/forum/showthread.php?123861563-Maintenance-Mode-for-2016-2017-CX-5-electronic-brakes/page2
this happened to me, I didn;t adjust it correctly and it was a little offset and the piston kept pressing on the pin instead of the rear pad... the clanking noise was the piston slipping on the pin and slapping the rear pad

I think this groove was just a carry over of old CX-5's before 2016, any CX-5 before 2016 had the manual hand pull brake and no electronic parking brakes and those needed to rotate to get the pistons back, in 2016-2019 CX-5's you must enter maintenance mode first , if not and you just push back with a C-clamp you may break the motor and that's a huge repair bill.

Sorry for so many questions. But I am curious about why it shouldn't be rotate and how the rotation actually work for this brake.
 
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It's a 2016 CX-5. And yes, I am talking about the piston boot in picture.
I use a spreader tools to push it back,
----
Capri Tools Swivel Brake Pad Spreader Tool
https://www.amazon.com/dp/ (commissions earned)
----
Is the piston boot sealed?

It sound like I can enter maintenance mode, rotate the piston in direction to untwist the boot and also keep the notch pointing directly up, then push it back directly without rotate. Feel like it's a safer way without risking cut it.

Thank you for answering my question. Will try to do it later today.

Update - seems it improve braking a bit. Is it possibly the reason ?
 
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My CX-5 is a 2016 and the TSB does apply. I am going to call the dealership tomorrow to see if they will update the rear calipers, but the car is out of warranty with 75k mi on it.

Here are US VIN ranges:
US (2016 MY) MEXICO (2016 2017 MY) JM3 KE **** ** 600015 - 866136

Mine is under the 866136 VIN range. I am going to be doing a test on this. I am out of warranty in August end.

Just curious if either of you were successful in getting the TSB work done past the 3/36 warranty?
 
Hello, needed to register to be able to ask a question about my issue. I have a Mazda CX-5 2016. I've been having an issue with the driver's side rear brake and determined the pads were shot and the rotor was beginning to wear badly. I was finally able to get some time to attempt to replace these.

I got my car in the maintenance mode described in this thread. I got the tire off, got the caliper with the EPB motor off, and I disconnected the EPB connector. After which I was only able to merely replace the pads as I could not get the rest of the caliper off to replace the rotor. At that point I figure I bought myself enough time to get it somewhere they could do the full work on both rear brakes. I got the piston back into the caliper without rotating it as mentioned here as well. Reapplied the caliper and reconnected the connector. After which, I just needed to the wheel back on and exit maintenance mode.

This is where I ran into a problem. After getting the wheel back on, I had a bunch of dash lights on and errors on the info readout. They main ones being keyless system malfunction on the readout and the red brake light warning on the dash. I replaced the battery in the fob, but the issue persists and I cannot get the car out of maintenance mode or even start it as it doesn't seem to recognize my key anymore. Note that it did recognize the key for a short time after I changed the battery in the fob and i can still operate the locks remotely.

Anyone have a clue what I screwed up or is the an issue I'll need a Mazda Dealership/Garage to fix?
 
Hello, needed to register to be able to ask a question about my issue. I have a Mazda CX-5 2016. I've been having an issue with the driver's side rear brake and determined the pads were shot and the rotor was beginning to wear badly. I was finally able to get some time to attempt to replace these.

I got my car in the maintenance mode described in this thread. I got the tire off, got the caliper with the EPB motor off, and I disconnected the EPB connector. After which I was only able to merely replace the pads as I could not get the rest of the caliper off to replace the rotor. At that point I figure I bought myself enough time to get it somewhere they could do the full work on both rear brakes. I got the piston back into the caliper without rotating it as mentioned here as well. Reapplied the caliper and reconnected the connector. After which, I just needed to the wheel back on and exit maintenance mode.

This is where I ran into a problem. After getting the wheel back on, I had a bunch of dash lights on and errors on the info readout. They main ones being keyless system malfunction on the readout and the red brake light warning on the dash. I replaced the battery in the fob, but the issue persists and I cannot get the car out of maintenance mode or even start it as it doesn't seem to recognize my key anymore. Note that it did recognize the key for a short time after I changed the battery in the fob and i can still operate the locks remotely.

Anyone have a clue what I screwed up or is the an issue I'll need a Mazda Dealership/Garage to fix?
Not sure which part youd screwed up caused many more issues. But one thing for sure is your rear brake problem is caused by inferior factory rear brake calipers which is a known issue described in the following TSBs:

TSB 04-005/16: Noise from Rear Brakes Due To Brake Drag

TSB R052/16C - Noise from REAR BRAKE/Trace of Rear Brake Dragging

2016 rear brake TSB resolution

You need revised version rear brake calipers to truely fix your rear brake problem.
 
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So I sent my car to a Mazda Garage. Found the issue with it not starting. Car battery was basically dead.

I know this might seem like a basic step not worth mentioning, but perhaps the original post should be edited to tell those of us rookies that you turn off the ignition power after it's put in maintenance mode. Lesson learned on my part the hard way.

I'm sure some are reading that saying "what a dope" but I was not sure I was suppose to turn the car off after putting it into maintenance mode. Took the instructions a little too literal.
 
So I sent my car to a Mazda Garage. Found the issue with it not starting. Car battery was basically dead.

I know this might seem like a basic step not worth mentioning, but perhaps the original post should be edited to tell those of us rookies that you turn off the ignition power after it's put in maintenance mode. Lesson learned on my part the hard way.

I'm sure some are reading that saying "what a dope" but I was not sure I was suppose to turn the car off after putting it into maintenance mode. Took the instructions a little too literal.
Thanks for clarify your situation. I still believe youve only fixed the problem on surface to your rear brakes, and the same problem will re-occur again and again due to the EPB dragging issue. Even worse, the rear brake could totally lock-up on the highway if you dont replace your factory rear brake calipers with new revised ones.
 
Is it necessary to go into maintenance mode if all you're doing is re-lubing the caliper slide pins and not pushing in the piston?
 
Here are 3 out of 5 files Anchorman had posted in another thread on rear disk brakes with EPB for 2016+ CX-5 from Mazda CX-5 Workshop Manual:


DISC PAD (REAR) REPLACEMENT
52CF0892-7438-47F0-8548-D234E9674FCD.jpeg

39C7DF07-8BD0-4C56-BAD9-22839EA64172.jpeg

F737DECA-684A-4603-AF43-1AC525ABE07A.jpeg

CALIPER (REAR) DISASSEMBLY/ASSEMBLY:
E667CAE6-A478-47B5-84AB-610B5B57969A.jpeg

82F05328-5A43-41C6-88F9-6A64FF6994E8.jpeg

ELECTRIC PARKING BRAKE MOTOR GEAR UNIT REMOVAL/INSTALLATION:
2BDB3000-B832-48A4-9CD1-9179F77E4B58.jpeg
 
This valuable thread by tomcat1446 is used to be under now defunct “How To” section and it’s easy to be found. Now it’s buried in the “General” section without the ”Guide” heading for some reason. Hope the mod can move this to a proper and easy to be found (sticky?) place.
 
Is it necessary to go into maintenance mode if all you're doing is re-lubing the caliper slide pins and not pushing in the piston?
I don't think so. I relubed my caliper pins just by unbolting one side to swing the caliper away from the disc.
 
ok folks,

I tried to make a video but it's too hard for this procedure, I needed to use both hands, so I'll write up a detailed procedure based on the Mazda PDF's provided by Anchorman (much thanks) see post # 12 of this link: https://www.mazdas247.com/forum/showthread.php?123861543-2016-cx5-rear-brakes

The purpose of the maintenance mode is to back off the EPB motor so you can compress the pistons easily (DO NOT TURN THE PISTON)

I can see how it is tempting for someone who doesn't know about these EPB to use the Lisle 28600 tool to try and turn them back in BUT IT WILL NOT WORK, the motor will not allow it, forcing it with a C-clamp will break the EPB motor. The motor must be backed off first with the procedure below.


I believe the dealer can use a scan tool computer to have the car enter EPB maintenace mode, but at least Mazda gave us an option for those who don't like going to the dealership with this procedure below. Without this procedure we would be at the mercy of the dealer to get the EPB motor to retract if we wanted to replace rear brake pads.


there are little nuances some people might miss so I add my notes in red............

Switching On Maintenance Mode

1. Switch the ignition ON (engine off). (you have to press the start button TWICE) pressing once only gives you ACC power, (do not press on brake otherwise engine will start, engine must be off)

2. Release the electric parking brake. (to release the parking brake, you have to have your foot on the brake pedal, then press down on EPB switch to release it, you will hear the motor releasing and the light on the EPB switch light goes off)


(I'll simplify remaining steps here: after step 2, release foot from brake pedal, and move over and press accelerator pedal down fully and press down on the EPB switch at the same time and hold, then press the start button 3 times quickly, you will hear the motor moving and the yellow parking brake with exclamation point light up) you are now in maintenance mode.

Now go do whatever you need to do on the brakes, for the rear brake pistons DO NOT TURN THE PISTONS, compress them straight back like you would do the fronts. After they are compressed back make sure the grooves are lined up in perfect North South orientation per Mazda instructions use Lisle #28600 for minor adjustments only.

Even if you don't plan to do your own brakes, it would be a good idea to let your mechanic know about the maintenance mode. They might not be aware and turn the piston which may damage the EPB motor.







Ending Maintenance Mode

1. Switch the ignition ON (engine off). (you have to press the start button TWICE (do not press on brake otherwise engine will start, engine must be off) pressing once only gives you ACC power

(I'll simplify the remaining steps here: press accelerator pedal down fully and pull up on the EPB switch at the same time and hold, then press the start button 3 times quickly, you will hear the motor moving back and the yellow parking brake with exclamation point goes out)

you can then move your foot and press on the brake pedal and pull up the EPB, you will see the normal red brake light light up and you're done.
It was very helpful, thank you.
 
This is possibly a stupid question, but is it possible to drive the car if the EBP system is in Maintenance mode? I have had a situation where my caliper failed to release all the way and was dragging. It occurred to me that putting the system into maintenance mode might release the system all the way and clear up the issue, but if it starts to reoccur I wondered if it would be an option to just disable the EBP by putting it in maintenance mode until I could get to the mechanic.
 
FYI, folks, the procedure outlined in OP for maintenace mode works on 2021 cx 5. Pistons were not too hard to push back into cailper, could do it with my hands.
 
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