I was going 10mph to stop in front of my daughter's school to pick her up when my brakes were difficult to apply. I had to use both of my feet to stop my car from crashing into the car in front of me. I heard a hissing sound when I applied my brake. The lights on my dash ABS lit up and then my car shut off. I was scared and didn't know what happened. I waited a few minutes when no one was in front of me and tried to drive away and it happened again. I left my car at a gas station for a tow truck to get it. I waited for the car to be towed and googled what happened. Turns out over 50 other people have had the same issue happen with the same car and year. The brake booster assembly went out between 43000-50000 miles. Some scenarios were worse than mine. They were driving faster than 10 mph and could not stop the car in time or at all. There is no recall and the dealership said because I moved to guam from Washington I had to pay out of pocket for the repair. I had it replaced and in December and still have not been able to drive it. The part they replaced is faulty too. And they ordered a new part. So its sitting till the part arrives on the island of guam. This site I was on has lots of people with similar issues with the brakes. Please look into this. The brakes are a big issue in a car. Https://www.carcomplaints.com/Mazda/Cx-9/2012/brakes/service_brakes.shtml

- Hagatna, GU, USA

Brakes do not stop vehicle immediately, it is hard to apply brakes.

- Bradenton, FL, USA

The Mazda CX9 that we purchased has a acceleration problem when we go to stop.. Mazda has never been able to solve the problem completely.. we have had 2 brake boosters replaced under warranty. We feel the car is unsafe to drive and Mazda has not addressed the problem. They tell us nothing is wrong with the car. It know also has transmission problems with squeaking and grinding noises coming from the car. This is a design flaw that has not been addressed.

- Desmoines, WA, USA

Airbag safety recall, transmission switch failure, throttle body failure, brake failure

- Indianapolis, IN, USA

Power booster master cylinder failure. First, spongy pedal attributed to master cylinder with no fluid present. After refilling hydraulic fluid, pedal was better for a day or two then loud noise coming from cabin in vehicle when pedal is depressed. (it goes to the floor and becomes very loud.) sounds like an identical problem to earlier model year.

- Indianapolis, IN, USA

Brake booster, hissing noise and hard brake. No warning, brakes don't stop well. Brake booster continues losing vacuum pressure as long as the brake is applied. I have noticed online multiple complaints and a known problem.

- Decatur, AL, USA

Hissing sound when braking in motion or parked. When driving up to an intersection after exiting the freeway about 20 mph car would not stop no matter how hard I stepped on the peddle. Luckily I was able to slow before hitting the car in front of me. When stopped at a light car lunged forward while my foot was on the brake. This happened again while I was waiting for my daughter at school. It lunged up and nearly hit the car in front of me! scariest thing in the world to not be able to brake!!

- Vancouver, WA, USA

When braking the brakes are either hard and do not work or brakes are spongy, will slow vehicle, but will not give you confidence that they will stop the vehicle like they should. When braking at times you can hear a hissing, maybe all the time, but when things are happening you aren't listening for a hissing sound. Also, when the vehicle is stationary and in park if you really put you foot to the floor a beeping almost like an alarm sound is made. This brake booster failure should be a major concern. 8-13-2017 I was traveling about 65 mph in lite traffic on a downgrade and slight corner when a vehicle in front of me lost a tire and I needed to brake quickly and my brake pedal wouldn't move, it was hard as a rock, never slowed the vehicle at all. Thank goodness I had plenty of room to maneuver, otherwise who knows what the result of that accident may have been. Another time was 8-30-2017 I was driving my vehicle, approx 20 mph, and was approaching the intersection of our subdivision and the hwy where the traffic travels at 55 mph, I went to brake and the pedal went to the floor.... again no brakes. My vehicle rolled to a complete stop, but not before I crossed into the second lane of cross traffic. Again thank goodness it was around 6:30 am and traffic was fairly lite. Mind you this is only two of the more extreme times. I have purchased a new brake booster and it will be installed this weekend. I did try to contact Mazda, but after sitting on hold, 1-800-222-5500, for over 18 minutes the phone finally rings.....until it disconnects.

- Sparks, NV, USA

When stepping on the brake peddle a hissing sound is heard and the brakes no longer stop the car.

- North Charleston, SC, USA

The car breaks became hard to push started hissing and wouldn't respond to break till the pedal was almost pushed to the floor. There was no warning. We were on the highway.

- Salem, MA, USA

Brakes have become very squishy and unresponsive and there is a hissing sound when depressed. This is a 2012 Mazda but it only has 23.5K miles on it. This happened all of a sudden and without warning and makes the vehicle very dangerous to drive. It is becoming progressively worse, will be taking to the dealership for repair under supposed extended warranty.

- Dallas, TX, USA

My brake becomes really stiff when pushed. This specially when coming to a stop where you have to use all your energy to make the car stop. My wife use this car with 2 young kid 5 and 1 and one on the way. This really worries me specially that its happening to a lot. It may not seem a lot to Mazda but its a lot for the consumers specially when lives are at risk. Pls fix this problem before its too late. I was even thinking of trading to the new 2017 Mazda but now I have doubts

- Chula Vista, CA, USA

The contact owns a 2012 Mazda Cx-9. while driving various speeds, the brake pedal was depressed and failed to engage correctly. The pedal felt stiff and there were no warning indicators illuminated in the vehicle. The vehicle was taken to an independent mechanic who diagnosed that the brake booster was faulty and there was a leak in the master cylinder that needed replacement. The vehicle was repaired. The manufacturer was notified and opened a case. The VIN was invalid. The failure mileage was approximately 100,000.

- Maysville, KY, USA

My break pedal feels as if it becomes stiff and I hear a hissing noise coming from the pedal. My breaks will not slow the vehicle. I have to remove my foot and reapply pressure forcefully in order for the breaks to work. It does this in reverse, going down an incline or flat surface. This happened while my child was with me. Please repuireva recall or lives may be at stake.

- Maysville, KY, USA

Brake pedal intermittently will not depress and will not stop the car from going forward. Brake reservoir full. Multiple times during a single drive. Very unsafe.

- Whitesburg, TN, USA

Without warning the brakes became spongy and difficult to depress the pedal. Stopping distance significantly increased and a hissing noise while brakes pedal depressed. Took it in for evaluation and diagnosed with brake booster failure.

- Napa, CA, USA

Brakes failed. Attempts to stop only slowed vehicle down unless extreme pressure applied. Pedal stopped halfway. Occasionally ABS activated due to excessive force required to depress brake pedal. Repair with replaced brake booster. Immediately failed again by making noise on depression though vehicular is stopping. Dealer ordering another booster and will need to return for repair again when it comes in.

- Lahaina, HI, USA

Brakes are hard to push. It feels as if pressure is pushing up as I push down

- Largo, FL, USA

Brake pedal suddenly became very stiff and hard to depress. Car was in motion and occurred as I was slowing down from 30mph to 20mph to enter an active school zone on a residential road. After coming to a standstill and repeatedly depressing the brake pedal a hissing sound could be heard emanating from the brake pedal area.

- Plano, TX, USA

Upon driving my vehicle, it became very difficult to stop at all times. I had to use both feet to stop at a emergency stop and almost hit a car pulling out in traffic. There was no stopping this vehicle using the breaks. I have my two small children that travel with me, this problem was a huge threat to their safety and lives. This problem needs to brought to the attention of other drivers before it is too late. Before my car caused an accident, I brought it to my mechanic and he told me it was the break booster. He also told me that this should not be happening considering the age and mileage on my vehicle. He did some research and found several complaints related to this issue, but no recalls. With no other choice I had him fix the problem. This is a huge safety problem and should have a recall. I would like to be reimbursed for the mechanic I paid to fix the problem. If it wasn't for the defect in the break booster, I wouldn't have had this problem in the first place. My questions to you are, how many people have to have their lives and loved one's lives put at risk in order for a recall to be issued" is it cheaper to have a law suit or to issue a recall"

- Gloucester City, NJ, USA