On 24 July 2015, while driving home from work, the driver in front of me executed an emergency braking to avoid a collision which caused me to do the same. From the moment I tried to actuate the brake pedal, it felt as if the pedal was in the floor and immovable. Little, if any, brake force was applied and required both feet with all the power of my legs to get even a small amount of braking. I had to immediately dive into the median at speeds of 60-65 mph to avoid hitting the car in front of me. This caused two tires to have to be replaced. When I left my parking garage and all the way to the freeway, braking was normal. No dash lights were active nor are they now. The issue persists now and driving the vehicle is not an option.

- Glendale, AZ, USA

Brake pedal is very hard to push in. Tried to stop at a light and the brakes wouldn't stop the car, luckily there was't someone in front of me. Brakes feel like I am pushing against a wall, also can hear a hissing or leaking sound when I try to push the brakes.

- South Jordan, UT, USA

The brakes did not respond to typical pressure required to stop... when I pushed harder on the brake pedal it felt like the brakes were starting to engage, however I could not get them to fully engage and stop in time to avoid rear ending the vehicle in front of me. I took evasive action and jumped the curb and directed the vehicle at bank of newspaper stands in order to come to a complete stop.

- Las Vegas, NV, USA

I have been having issues with the brakes mostly when raining or snow. At times when I go to hit the brakes they get stuck or make a grinding noise and don't want to stop. This has happened numerous times and almost caused me to hit another car on multiple occasions. I will take it in soon to have it checked now that I see that I am not the only person with this issue. Starting in Jan 2015 I notice a burning smell coming from under the hood of the car. I had an oil change and checked for an oil leak to find nothing wrong with the vehicle. After running the car for at least 20 minutes the smell continues.

- Hyde Park, MA, USA

Vehicle would not slow or stop, had to push pedal hard all the way to the floor to get it slowed. Really thought we were going to have an accident. Took vehicle into shop on 6/5/2015 and was told it was the power brake assist module was bad and needed to be replaced. Owner of shop said we were lucky to not have been in an accident. Come on Mazda you are aware of this situation.

- Stafford , VA, USA

I had 3 children in car seats, myself and my oldest son in our CX9. I crested a hill and started down the other side and I applied the brakes to slow down and they were hard and would not allow me to stop. I almost hit the truck in front of me. He was thankfully watching his mirror and ran a red light to get out of the way so I didn't hit him. After standing on the brakes for what seemed like a life time they finally engaged in the middle of the intersection and hissed with a loud squealing noise. I removed myself from the intersection and at 5 miles per hour went to the nearest mechanic. I was told to call Mazda because the power assist braking system had failed. I called Mazda and they told me not drive it as it was unsafe. They would have it towed to the nearest dealership and would take care of it. The nearest dealership is dolan Mazda Kia in reno Nevada. I was informed by steve to look at it in the shop I was looking at $125. And that it was no longer under warranty because my CX9 has over a 100K mls. And the warranty ran out at 90K. The brakes failed unexpectedly with no warning. I was never notified about this safety issue from Mazda nor the dealership I purchased it from. I see that the NHTSA has closed it's investigation with no recall or that Mazda customers were informed. My family could have been seriously injured or even killed.

- Winnemucca, NV, USA

Brake booster goes out causing brakes to unexpectedly malfunction and not stop the car in a timely manner. Brakes become hard to press, sound of hissing air from under dashboard, brake pedal was pressed all the way to floor and still did not stop the car in a safe manner. No warning lights alerted to this problem prior to this incident.

- Winchester, KY, USA

I noticed a hissing noise when I press the brake pedal. It goes away when I let off the brake. I haven't noticed a difference in the brake pedal but I will be paying close attention to it. This is a major safety issue and should be recalled asap. I have 2 kids that ride in this car. I called the dealership and have an appointment tomorrow. The service department said they heard about this issue but haven't had a repair like this yet. I will update what I find out.

- Virginia Beach, VA, USA

This is the second happened to my Mazda CX9, 2011. The brake started to have hissing sounds while stepping on brake. The brake pedal is harder than usual to depress. The brake functions has been reduced around 30~50% less than normal. This has put deriving safety in jeopardized. This is the second time my CX9's brake booster failure. The first time is in year 2012. I worked with Mazda to have brake booster replaced. However, dealer seemed not realized there is a warranty extended program from Mazda --- Mazda special service program -93 (ssp93). This is official recorded in NHTSA action number PE14005. Dealer tried contacting Mazda for this program. But Mazda kept not responding, it has been two weeks but still not message back from them. I paid the repairmen of the defective brake booster (parts & labor) from my own packet at this point. Despite the defective parts for jeopardizing driving safety, my complaints to Mazda is also for their non-responsive to customer's warranty program which they have made.

- Dededo, GU, USA

I actually noticed when I started my vehicle up and pressed on the brake pedal, it seemed to slowly sink all the way to the floor and made a hissing noise. The noise only stopped when I took my foot off the brake pedal. As I was driving, on several occasions I had dramatically reduced stopping performance when applying the brake. I've gone through several stop signs and have almost rear ended other vehicles. This seems to have suddenly happened, I first noticed it on 3/1/15. This wasn't happening on or before 2/26/15. I suspect the power booster or master cylinder have failed, though I'm concerned that this happened with only 61,000 miles on it.

- Haslet, TX, USA

The contact owns a 2011 Mazda CX9. While driving at low speeds, the contact heard a hissing noise coming from the front brakes. While attempting to engage the brakes to stop the vehicle, the pedal sank to the floorboard. The dealer stated that the brake booster was faulty and needed to be replaced. The brake booster was replaced and the failure was remedied. The manufacturer was not notified. The failure mileage was 43,000.

- Gibsonia, PA, USA

The brake booster failed. All of a sudden the brake felt hard and the car wouldn't brake - had to press very hard to barely avoid hitting another car in front. On the way to the dealer, it was scary and could have easily got into an accident. I am lucky it didn't happen on a highway. The dealer replaced the brake booster - it was under extended warranty but not recalled. Though the dealer was quick to fix the problem, I believe this is a really dangerous and lives can be lost! I expected a defective braking system should have initiated a recall!!!

- Wayland, MA, USA

I went to have new tires put on the car and on the way to the tire shop when I applied the brakes the peddle became hard and was difficult trying to stop the car.after the new tires were put on the same thing on the way home, still has a hard brake peddle when the brakes are being applied.

- Phoenix, AZ, USA

I was driving about 40mph when I pressed on the brakes and it was hard and would not stop. I stepped on the brakes several times when it finally slowed down but it slowly rolled to a stop. After a few days of driving like this I knew to start breaking way in advance but now the car would suddenly turn off when at a complete stop while waiting at a red light. The whole engine would turn off and the engine light would turn on. I would turn the engine key off and then turn it on and the engine would turn on after the second try. I was freaking out every time if got into the car because I knew it would stop on me whenever I would stop at a long stop light. I finally took my car to a Mazda service center and they said it was the brake booster. It's been 5months and my car is running great. I hope this is the end of this brake booster nightmare because it was a really scary experience.

- Downey, CA, USA

Without warning, the brakes failed. They seemed locked to the floor, impossible to press. No signal indicators no warning. Just suddenly no brakes. Very critical problem and accidents involving loss of life is probable.

- Arnold, PA, USA

Brakes makes a hissing sound when you step on it and it is hard. Updated 03/4/2015

- Lilburn, GA, USA

The contact owns a 2011 Mazda Cx-9. while decelerating from approximately 55 mph, the contact noticed that the brake pedal was difficult to depress. The vehicle began making a hissing sound and the check engine indicator illuminated on the instrument panel. The vehicle was not diagnosed or repaired and the manufacturer was not notified. The approximate failure mileage was 57,119.

- New Haven, CT, USA

I was going approx 40 mph, and went to hit the brake pedal at a light, and the brake pedal was incredibly hard and would not push down. I lifted my foot up and tried again. The pedal was still very hard but I was able to push (very hard!) and get to a stop. I did stop pass the light as it took me longer to stop the car, but luckily there were no cars ahead of me, nor any going through the intersection.

- Round Rock, TX, USA

First I was backing out from a parking spot and almost hit a car waiting behind me because the car did not stop, I first did not think anything of it, I thought I did not step on the brakes well, but after while driving I noticed that it was hard to break at the red light...I decided to drive home, and my car would not stop and was rolling the stop signs, no matter how hard I stepped on the breaks the car would not stop!!!!!!!!!!!! this was very scary, I thought I was going to crash. I tried pumping the break and would hear some type of air coming out form underneath. They need to recall all of these vehicles! I could have killed myself or someone else crossing the street!! I am now afraid to drive it even though it is at the dealers getting fixed.

- West Hills, CA, USA

The brake pedal has become extremely hard and it doesn't stop quickly anymore. It feels like the brakes are going to completely fail and not stop the car. A car in front of me suddenly stopped to make a left turn and as I applied my brakes, they became very hard and took a very long time to stop, I almost rear ended the car ahead of me.

- Wanaque, NJ, USA