The contact owns a 2012 Mazda Cx-9. while driving approximately 35 mph, the brake pedal was depressed and a loud squealing noise emitted. After applying the brake pedal numerous times, the vehicle came to a complete stop. The vehicle was towed to the dealer and currently being diagnosed. The manufacturer was not notified of the failure. The approximate failure mileage was 95,300. The VIN was unavailable.

- Las Cruces, NM, USA

I noticed that at very slow speed (backing out, easing forward) the brake pedal was very hard, did not depress, and car was difficult to stop. I did not have much of a problem at regular (60 mph) speed. Only once was there a loud hissing on the drivers side when the pedal was depressed. The dealer told me brakes were fine but the car did not drive fine. I took it to my mechanic who told me I needed front brake pads. Upon changing brake pads, I was told the brake booster was bad and causing the pads to wear abnormally fast and that the problem was actually worse with the new pads. Definitely a problem as I was only at 31,000mi. I didn't not return to the dealer and had the mechanic do the repair right then. What I thought was minor maintenance turned into a $500 repair. I found out later that there is an extended warranty of 7yr/90,000mi on the brake booster if diagnosed and fixed by a dealer.

- Lawrenceville, GA, USA

The brakes do not work. When I initially depress the brake from park to drive, the car begins to roll as if I did not have my foot on the pedal. I hear a hissing sound now when I depress the brake. The brake system has rapidly deteriorated in just 1 week. Sometimes, I am not able to stop the vehicle at all. I will be taking my vehicle back to the dealership tomorrow. 4.9.16

- Fort Worth, TX, USA

My wife complained to me about her brakes becoming hard to the point she couldn't stop the car. I then took her car for a drive and while in motion I hit the brakes and the brakes became so hard I had to use an unreasonable amount of force to get the vehicle to stop. The vehicle also has really diminished stopping power when this occurs. This seems to occur when more frequently when the brakes are pushed more than once in a short period of time such as stop and go traffic.the vehicle also makes a hissing noise when the brakes are applied. I believe that this could be a bad brake booster. I feel it is a safety issue and may cause an accident.

- Rimersburg, PA, USA

The brakes have become very difficult to push. They slow down the car, but require intense pressure to bring the vehicle to a complete stop. There is also a slight hissing noise when the brakes are applied. It takes about twice the distance to come to a complete stop than previously. There is no indication of a problem on the dashboard; no warning light has been displaying, but something is definitely wrong. I do not feel very safe when driving.

- Erda, UT, USA

The vehicle presents a catastrophic failure in the brake system. The brake pedal gets extremely hard to depress and the effect is minimal. The vehicles stopping distance is significantly increased; if pressed harder the pedal will suddenly get softer and the brake power increases unexpectedly jerking the vehicle to a stop. Additionally, there is a loud hissing noise noted when the brake pedal is depressed. The hissing noise comes from the drivers side of the cabin in the vicinity of the emergency brake pedal. Mazda needs to address this issue as many people have identified concerns in this area. Of course we operate utilizing tombstone management theories; only recognizing a problem once someone is killed.

- Fayetteville, NC, USA

The contact owns a 2012 Mazda Cx-9. the contact stated that once the brake pedal was depressed, an abnormal sound could be heard. In addition, the brake pedal descended to the floorboard. The failure occurred without warning. The vehicle was taken to the mechanic where it could not be diagnosed. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 62,000. The VIN was invalid. Updated 03/18/16

- New Port Richey, FL, USA

Brake pedal makes hissing sound when depressed like air leakage; intermittently very difficult to depress brake pedal with a lot of force applied (typically if pumping brake), leading to increased stopping distance/difficult stopping. Occurs when brakes depressed (soft pedal, air hissing); if depressed again in quick succession, very hard to press with significantly reduced stopping power. Occurs whether vehicle standing or in motion.

- Ypsilanti, MI, USA

On January 7,2015 I was driving on the long island express way merging off the ramp back onto the high way when I couldn't break. My breaks didn't work. I kept on pressing them down and nothing was working. Trucks were all honking at me because I was merging without stopping. Finally I went off the ramp onto the grass. I called the dealership and was informed that there is a recall regarding this problem. Never got anything in the mail from them stating of such thing.I took the car in and I don't own the car anymore because I was beyond afraid after this situation.

- New York, NY, USA

The vehicle presents a failure in the brake pedal, which gets harder to press and the brake power is diminished, if pressed harder the pedal will get softer and the brake power increases but the sensation of reliability and safety when braking is affected. Also, when the brake pedal is depressed hard a hissing sound is heard.

- Katy, TX, USA

My brakes are failing. I first noticed the brakes were spongy and there was a hissing sound in the cabin. Then the brakes became very hard. I was very afraid I was going to hit vehicles in front of me. Also, eventually the car would die when the brakes were applied. The Mazda dealership told me it is the brake power booster. This is very common. Please, please recall these vehicles. I bought this vehicle used and it would have been nice to know about this dangerous problem.

- Denham Springs, LA, USA

Car would not stop when backing out of garage. The brake pedal was stiff causing the car to roll off the driveway and into the side yard. We tried to drive the car back into the garage but the brake pedal resistance was inconsistent - from firmer then usual to less firm - making it difficult to stop the car. When the brake pedal is pressed, a "hissing" sound is audible. The Mazda dealership determined the brake booster was losing vacuum. The dealership replaced the brake booster. This is a known Mazda issue, but they continue to manufacture this car without a correction. There should be a mandatory recall. The dealership was not able to tell me definitively if the new brake booster has this flaw corrected. This issue could cause a fatality.

- Mason, OH, USA

As I was driving I noticed my brakes making a hissing noise of about day. Then, the brake pedal became hard and they failed to work.

- Pompton Lakes, NJ, USA

Brakes prematurely failed after feeling numb and squishy. Upon diagnostic by a local mechanic, it was determined that the brake master cylinder had a leak. In addition, the ABS, traction control and emergency brake lights came on when the symptoms were present. Estimated cost of repair $1250.

- New York, NY, USA

Car of 3yr 8mth < 40K mi. Brake not effective, fade very quickly, attempt to lift and reapply brake makes thing worse. Harder to brake. Hear hissing noise, similar to complained by others here. Mazda needs to recall before someone gets killed.

- Sugar Land, TX, USA

When applying brakes, brakes do not stop completely. There is a hissing sound when applying brakes. Brakes feel harder to press than usual.

- Poocomoke City, MD, USA

We experienced what similar Mazda CX9 owners have reported: Our brakes stiffened, provided resistance coupled with a hissing noise, and failed to stop the vehicle in a timely manner, despite having a full brake fluid reservoir and sufficient brake pads. Our mechanic reports failure of the master cylinder and the blower. We experienced these events suddenly and while the car was in motion.

- Adger, AL, USA

Brake pedal got hard vehicle would not stop no warning lights almost rear ende vehicle brake failure

- Bradenton, FL, USA

Brakes making hissing sound and the car suddenly stalled while waiting on a light. After sometime car started but brakes were hard and had to press really hard for car to stop.

- Torrance, CA, USA

My brake feels like it has air under it and is hard to press down on. It also makes a hissing sound. When stopped at a traffic light, with my foot on the brake, it feels like my car is trying to move. I am scared my brake will fail or not work when I push on it. I noticed this about a week and a half ago. I thought it was nothing at first but it is still doing this and more frequently. I am concerned that this will cause an accident. I am worried something will happen to my children or me if my brakes fail because of this.

- Thibodaux, LA, USA