Mushy brake pedal (2006 Mazda5)

I agree with silentnoise, it's probably something to do with your ABS. A faster/cheaper way to clear your ABS may be to activate it by slamming on your brakes on a slick service. This should activate the ABS and cycle new fluid thru it. At least this is what I read :). It still doesn't hurt to lube your caliber pins as they do get stuck.

edit: by the way, how did your mechanic bleed the brakes?
 
Explained in detail. You are not going to like what you hear... :(

https://www.youtube.com/watch?v=0r46_unyYk8

Yes Ive been hoping it would not be the ABS but all the symptoms point to it being the problem. Unless bleeding the ABS can fix the problem. BTW which ABS control unit does my mazda 5 2009 GT have: with stability control C3Y7-43-7AZA for $950 or one without C2Y6-43-7AZB $390 (from realmazdsa parts.com? According to website they both fit my car. Are they interchangeable? Is the AZA an upgrade? I havent checked availability at the scrap yard but then again I havent gone back to the shop for additional diagnosis to check if this is really the problem. Thanks
 
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Yes Ive been hoping it would not be the ABS but all the symptoms point to it being the problem. Unless bleeding the ABS can fix the problem. BTW which ABS control unit does my mazda 5 2009 GT have: with stability control C3Y7-43-7AZA for $950 or one without C2Y6-43-7AZB $390 (from realmazdsa parts.com? According to website they both fit my car. Are they interchangeable? Is the AZA an upgrade? I havent checked availability at the scrap yard but then again I havent gone back to the shop for additional diagnosis to check if this is really the problem. Thanks
Do your model come with DSC? You should have a button on the dash panel, above your left knee, to turn it on/off. If your 'ca' is Cali, then you likely don't. DSC became standard equipment starting 2010 models. If 'ca' = Canada or other, don't know.

BTW, for folks who have this problem, have you ever serviced your brake fluid? I tend to think this is happening b/c of neglected brake fluid maintenance -you are suppose to change (not just bleed) it every 2-3 years. I remember before ABS, no body changes brake fluid. Top off as needed and go. Sure you had to brake a little harder but it works. I bought a garage queen Miata and the brake fluid reservoir has contaminants in it and strained the inner reservoir walls - but it works! Not the case anymore with more electronic doohickies in the system.
 
I had the exact problem on the 5 that I just traded for. Spent countless time bleeding brakes, checking for leaks, and even replaced the master cylinder. All to no avail. Then yesterday I picked up a used ABS pump from the local salvage yard for $75. Fixed! I guess if you were looking to properly diagnose you could get plugs for the master cylinder and then move down the line and get plugs for the ABS in order to isolate the problem. I had a hard time finding the plugs at any hardware store because the thread size is rare (M12x1.0).

Did you have to bleed the new ABS pump using a device when you installed it?
 
Finally able to put closure to this issue. And yes it was the ABS that was the culprit. My 5 never had any leaks and CEL/ABS light. Even dealer couldnt isolate the problem and wanted me to replace MC, all calipers, all brake hoses, and the ABS unit. While trying to solve the sinking brake issue I ended up replacing the MC and booster before finally the ABS. Got the part online and had a shop install it. Thanks for all the help.
 
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Did you have to bleed the new ABS pump using a device when you installed it?

Sorry I didn't see this. I had my neighborhood shade tree mechanic install the used ABS pump (1.5 years later its still working great and only 75 bucks plus 2 hours labor!). I'm pretty sure he doesn't have any fancy ABS bleed equipment. More than likely just bled at the furthest wheel first and eventually all the wheels (as he instructed me early on while I was initially troubleshooting).

The brake fluid was absolutely filthy when I first bought the car and so I can't help but think the reason many of us deal with ABS failures is the lack of checking/flushing the brake fluid periodically.
 
This is interesting. I've noticed a slightly mushy brake pedal on our '12 "5", and I assumed that new brake hoses might be in order even though brake feel is generally just like new after my brake job last week. My dealership had recently recommended a brake fluid flush, which I thought sounded just as pointless as a throttle body cleaning.

Then again, this is my very first ABS-equipped vehicle, and my last fuel injected vehicle (1987 Ford 5.0 EEC-IV) was swapped to a carburetor in 2004.



Anywhoo ... I'm confused by references in this thread to bleeding something called an ABS "pump". Is brake bleeding not done the same on this car as on a car with normal brakes?
 
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Brake fluid is hygroscopic (except DOT 5). Once the bottle's air tight seal breaks, it has a limited shelf life regardless of if/how you drive the car. The consistent heating/cooling from everyday braking accelerates wear. The brake fluid reservoir cap is not air tight.


Normal brake bleeding wont activate the ABS pump. Watch video in post #22 to get a sense of the ABS solenoid.
 
This is interesting. I've noticed a slightly mushy brake pedal on our '12 "5", and I assumed that new brake hoses might be in order even though brake feel is generally just like new after my brake job last week. My dealership had recently recommended a brake fluid flush, which I thought sounded just as pointless as a throttle body cleaning.

Then again, this is my very first ABS-equipped vehicle, and my last fuel injected vehicle (1987 Ford 5.0 EEC-IV) was swapped to a carburetor in 2004.



Anywhoo ... I'm confused by references in this thread to bleeding something called an ABS "pump". Is brake bleeding not done the same on this car as on a car with normal brakes?
My 12 pedal is as firm as they day I bought it new in 2011. I did new brake fluid once at 65K miles. Car has 101K miles now.
 
So basically, proper bleeding of an ABS equipped vehicle involves triggering an "ABS event" to get the fluid to cycle through all the ABS valves, which is normally done in the shop with a special scan tool designed to issue special commands directly to the vehicle's surplus technogeekery. Got it. (crazy)
 
I've experienced exactly the same issue as described in this thread: a softer pedal and a longer pedal travel distance after hitting a pothole got the ABS engaged. This happened a few times already and every time after a while, the brakes would restore their quality to a firm feel and short pedal travel distance.

I can go score an ABS module from a junkyard.
I also found this video: DIY How to change abs brake module on a 2007 mazda 5

How hard could it be to replace the module? Do I need to empty brake lines prior to replacing this module? Given that the ABS line valve is stuck open, I guess, there will be fluid in there, right?

Any advice?
 
All roads lead to @Maikel :D. FORScan can calibrate and bleed ABS valves/solenoids (individually!).
^post is a redirect b/c it touches on FORScan.
 
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