Maintenance Mode is only applicable to 2016 CX-5 or newer with Electrical Parking Brake.How difficult is it to replace the rear calipers?
It’s a TSB and It’d be hard to get free updated rear brake calipers if the CX-5 doesn’t have the new car warranty. If the rear brakes have had severe lock-up situation which had been reported several times, it may worth a try to talk to MNAO and hopefully they would at least partially cover the cost.If the OP has a 2016 requiring updated calipers,could they be replaced free at dealer as this is a known Mazda issue and Mazda has replaced them for those requiring updated calipers.
I was aware after I had one side off that the electronic parking brake was built into it. Is there anything different in bleeding the brakes on this car? Any help would be appreciatedI assume there is a story behind that comment. Hopefully you were aware that your car has an electronic parking brake built into the rear caliper. If you have not found and downloaded the service manual with the electronic parking brake maintenance mode info you can find all the details in this thread.
Put parking brake into maintenance mode to begin disassembly.
After everything is back together exit maintenance mode and then bleed the air out of the new caliper(s).
Ask if you need advice to bleed the new caliper(s). This is not rocket science, but a little experience helps.
Jmaz and yrwei52 are right to ask if this is a 2016 model car. Not sure why you are replacing calipers - but if it is because the rear brakes were dragging then you might get some financial help from Mazda since some 2016 cars had faulty rear calipers.
Tip for keeping the brake fluid from emptying from the reservoir while you change the calipers: Wedge a piece of wood between the bottom seat cushion and the brake pedal. Pushing the brake pedal down moves the master cylinder piston past the reservoir opening and effectively blocks the fluid in the reservoir from leaking down and out of the open brake line.
Re: bleeding the brakes
After the brakes have been taken out of maintenance mode you can bleed them as you would any other brake caliper. Maintenance mode uses the electric motor to retract the caliper piston so the caliper is fully open. Returning to service mode the electronic parking brake uses the motor to push the piston out again to just touch the pads to the rotor - and then retract slightly so the pads do not drag.
Pay attention to the orientation of the notches on the caliper piston because they need to line up north and south to mate with the brake pad.
After the electronic parking brake system is out of maintenance mode - back into service mode you will bleed as usual by using brake fluid to fill the caliper and push any air out through the bleed valve.
I'm going to assume you don't have a vacuum bleeder or a pressure bleeder. Make your own brake bleeder tool. You will need some clear tubing from a hardware store that fits tightly on the bleed valve nipple and a plastic bottle (empty 16 - 20 oz. pop bottle with cap). Drill a hole in the bottle cap that will be a tight fit to hold the tubing. Push the tubing through the bottle cap and so it is near the bottom of the bottle. Then add several inches of brake fluid to the bottle so that the tube will be submerged and cannot draw air.
Now you are going to coordinate pushing on the brake pedal and opening and closing the bleed valve. Note: Avoid pushing the brake pedal to the floor. Possibly put a block of wood or something under the pedal.
Ideally you will have an assistant to push the brake pedal while you open and close the bleed valve - but if you are working alone the process is nearly identical. Connect the tool you made earlier to the bleed valve and confirm the other end is submerged in brake fluid in the bottle. The typical method is to start with the bleed valves closed and pump the brakes until you have a hard pedal. Then open the bleed valve and ask your assistant to push the brake pedal. The assistant says pedal down and holds it. You close the bleed valve and repeat. Eventually nothing but clear brake fluid comes from the bleed valve. By yourself? Start the same way except after you have a hard pedal you open the bleed valve and move back to the brake pedal and push and release the pedal 8-10 times using full strokes at a steady pace. Go back and check the tubing, bottle and the brake fluid reservoir. If the tubing is solid clear fluid at the bleed valve you are done. Close the bleed valve. Make sure the reservoir does not run dry. Not sure if all the air is out? Then repeat.
Remember that if the car is on four jack stands then the reservoir is the highest point. If you wanted you could simply crack the bleed valves slightly and let gravity do the job over time. If you have bled the air out when you open the bleed valve gravity will simply push brake fluid out immediately. That is a sure sign that there is no air in that circuit.