Hello everyone- I'm posting this question again in hopes that someone has joined that might have an answer. My wife has a 2016 CX-9. About 4 years ago or so I did a rear brake job and all was good except the e-brake now will only work effectively if the car is off. If the car is still on, and the e-brake is engaged, only one side (passenger) will engage and I'm treated to a lovely blinking parking light, and a yellow P warning light.

However, if I turn off the car and engage the e-brake, both will operate with no problem at all and I don't get any dash warning lights. I've swapped over the motors from left-right but the conditions stays (passenger side works, driver only works if car off). The dealer wanted $75,000 to fix the problem (slight exaggeration but still a 4 figure repair).

I hooked up my simple ODB scanner and nothing showed up. I've already tried doing maintenance mode again (several times actually). Nothing seems to work and now a smart inspection station has said it won't pass until we get that fixed.

Thanks in advance!

 

A GUESS ONLY NOT ABOSULUTE BY ANY MEANS

First I recommend that you take it to at least a Firestone and get an estimate for repair which will also give you a better idea the issue.


Guessing ONLY and nothing more because brakes and service done by DIY often results in missed steps or quick none factory recommend servicing you may need to replace the complete caliper and sensors on at least the one if not both rear wheels. But as I said based on the limited information this is a GUESS ONLY based on a few customers having the same related issue after they attempted to perform a brake service on electric rear brake assemblies.

 

I took it to the dealer and they wanted to replace all the ECU and brake components (thus the high bill). Interesting you say Firestone because in my area Firestone doesn't have a great reputation for dependable diagnoses, but I can find a similar location.

You said other customers have the same issue. What was their solution? Calipers and sensors?

 

Like most retail places the reputation generally stems from a butt hurt customer that had to wait longer than expected, not really service-related smart savy and thought that the prices on labor and parts were to high be based no real data or information to compare the actual prices of parts and the basic labor rate in that area.
Firestone only allows certified auto mechanics to do specific services like brake and alignment. The other services are more for anyone that we could call a "grunt worker". It does not take a large brain to learn to change tires, install wheel , fluid changes and other services that a monkey can be trained to do?
I HAVE NEVER BEEN EMPLOYED AT ANY FIRESTONE SERVICE CENTER.

As for your independently owned Mazda dealer giving you an estimate of labor and parts replacement, they would have also had you read the Mazda Automotive Technicians findings and results to conclude the estimate. If not, then ask them for it!
If you don't understand any of it or how they determined any part of it you can post it on your thread with your personal information redacted out and or you can PM me and I will be happy to look it over for you.

Yes I have either worked on or assign one of our Auto Techs to service similar brake issues. However, there is no constant and each case is different. So the solution(s) vary from each case.

ASE