While driving, the car developed a brake malfunction. when the brake pedal is depressed you can feel the pedal pulsating and was not slowing down until you pressed harder then the brakes apply abruptly causing risk of rear ending. Upon pulling over to the hard shoulder the pedal pulsating/drumming continued to happen even though the car is completely stopped and is in parking gear. The symptom is similar to the service bulletin PIC5734A. [XXX] The car was driven to the nearest dealership 'Dublin Chevorlet' in Dublin CA and the car has been there for 4 weeks since GM is unable to help resolve the problem. I have reached out to GM and opened a support case. Case number [XXX] ]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- San Ramon, CA, USA

Vehicle does not allow driver to driven uphill when packed uphill but keeps rolling down the hill even upon being throttled. Also emergency brake goes not catch but locks the wheel. Chevy diagnosed the issues agreed is manufacture defect, parties contracted agreement singed for repairs at no cost. Upon arrival of parts Roseville Chevrolet wanted $4,500 be paid said it was out of warrantee contrarily with the written agreement. Presently I have minors cannot ride in the car. The car may also cause accident and injury to owner and other road users if not fixed.

- Auburn, CA, USA

1. Propulsion Power Reduced -AGAIN. We have had this repaired recently & it-??s back. Apparently it-??s -??not a problem-?? as long as check engine light is not on. Unfortunately, the engine light is on AGAIN - despite being reset. The car is not accelerating when needed. 2. -??Brake Assist-?? light is on AGAIN- and I do not have power brakes. It is hard to stop. Could we at minimum get accurate warning systems & repairs that work? 2.

- Cleveland , MO, USA

Stacia was driving the vehicle on September 20th on a residential street. She was driving at 25 MPH. All of the sudden the brakes slammed on by themselves and the car slammed to a stop. Luckily there were not any cars around, or there would have certainly been an accident. If this had happened on the Interstate or on a busy street there likely would have been a serious accident. The vehicle was taken for service and it was determined that the Brake Pedal Position Sensor failed. This was replaced by Eric Von Schledorn Chevrolet. Our concern is that the failure of one sensor could cause a potential catastrophic accident. We wanted to bring this to your attention in case others have had a similar issue, and a recall may be necessary.

- Whitefish Bay, WI, USA

The contact owns a 2013 Chevrolet Volt. The contact-??s husband stated that while attempting to park the vehicle while driving approximately 1 mph, the brakes would not function. The contact stated that the stabilitrak warning light was illuminated. The vehicle was not diagnosed or repaired. The manufacturer was informed of the failure and informed the contact that the VIN was not under a recall. The failure mileage was approximately 90,388.

- Yardley, PA, USA

The contact owns a 2013 Chevrolet Volt. While driving various speeds, the brake pedal was depressed and the vehicle jerked. The contact mentioned that the air bag warning indicator was illuminated. The vehicle was taken to South charlotte Chevrolet (9325 South blvd, charlotte, nc 28273, (704) 444-0109) where the brake modulator valve was replaced. The vehicle was repaired. The manufacturer was made aware of the failure. The failure mileage was 73,625.

- Charlotte, NC, USA

Inside rear brake pad material separated from the steel backing resulting in damaged brake rotors and erratic braking. All other brake pads in satisfactory condition. These were the oem brakes and rotors.

- Minneapolis, MN, USA

At low speed (under 5 mph) I stepped on the brake pedal and had no response. I stomped down with all my might and still had absolutely no response from either the power antilock nor the manual brake. The car continued forward with no slowing until it hit the car ahead of me, traveling several feet before doing so. I never felt any brake engagement including 'pumping' of the antilock or any slowing. I was on a city street and had been at a full or near full stop before letting off the brake to roll forward. I was going straight ahead. Brakes have been regularly serviced.

- Rochester, MN, USA

The contact owns a 2013 Chevrolet Volt. While driving 55 mph, the brake pedal was applied, but failed to engage. There were no warning indicators illuminated. When the contact shifted into neutral, turned off and restarted the vehicle, it operated normally. The vehicle was taken to allen gwynn Chevrolet (1400 S brand blvd, glendale, ca 91204, (844) 633-8153) where it was diagnosed that the brake pressure modulator valve needed to be replaced. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was 52,000.

- Tujunga, CA, USA

In an emergency braking situation on a city street to avoid a car I hit the brake pedal and it went to the floor, no pulse from the ABS system. Hit curb and bumper hit fence. Took car to service to learn ABS electronic controller failed. No warning light on dash of any kind. Have learned GM has issued a bulletin but no recall major safety issue. Cost to repair $2400. Car is in perfect condition, has been trouble free and has only 23,000 miles on it.

- Los Angeles, CA, USA

While driving in rush hour traffic this Chevy Volt's entire electrical system crashed causing me to crash right along with it. No brakes (antilock braking system fail)no steering or horn even worse...no air bags.... results: Multi-car collision with no fatalities but, several injurys.

- North Hollywood, CA, USA

This is the third incident since I had this car along with charging issue in the beginning of ownership this Chevrolet Volt has been been deem total from the accident that occurred on January 6 because of the steering locking

- Bay Point, CA, USA

While the brake pedal is pressed, if one side of the car goes over a pot hole, the car loses braking power and continues forward even though the brake pedal is pressed. For example, if the right front tire goes into a pothole while trying to stop at an oncoming red light, the car displays a message in red letters on the dashboard referencing low traction while simultaneously losing braking power. The car continues forward with no braking power even though I still have my foot on the brake pedal. It only recovers braking power after two seconds. Unfortunately, by then, it might be too late to stop. This has happened twice. This is obviously a dangerous software error with the traction or anti-lock braking system.

- Charlotte, NC, USA

The car's electrical / software issues caused (1) all of the windows to roll down in unison (in for repair 3 times to fix this one), (2) caused the car to not recognize that it was in "park", thus not shutting off, and (3) caused the car to lose power without touching any of the buttons on the console (I.e. the "drive" button or the "power" button). The latest incident occurred last Friday (August 1, 2014) when the car just lost power while I was driving at 65 mph on I-85 North at around 4:00pm. I had to get over from 4 lanes of traffic with no power at all in the car and luckily did so without incident. Onstar's diagnostics showed that the electrical system, braking system, engine, and other parts of the car showed the car needed immediate attention. I put the car in park and while still with onstar the dashboard lit up and the power button lit up too. I hit the power button and drove straight to the rick hendrick Chevy dealership in duluth. When I went to pick the car up later Saturday morning, I was told that there's nothing they car do because they can't recreate the problem. They have reflashed various ecus, but at the end of the day cannot "recreate" the problems and cannot fix them. So they just wipe their hands clean of these issues and act like they don't exist. (the service manager actually called me "ignorant" once and later apologized.) I pray it doesn't take people dying in these cars before Chevrolet and/or General Motors does something to fix them.

- Duluth, GA, USA

When in low gear (higher regenerative braking), when braking and going over some bumps, the regen braking stops causing a feeling of a lurch forward. A 'low traction" light appears. This causes a reduction in braking force of approximately 35bhp, a very unsafe condition. An anti-lock brake style pulsation of the regen should be employed, not a discontinuation of the regen brakes.

- Manchester, NH, USA

Driving in los angeles consists of lots of uneven roads full of potholes. As I was trying to come to a complete stop while hit an uneven road and a pothole I temporarily lost control of my brakes and it felt like my vehicle was sliding. It was a brief 2-3 second feeling but very unsettling.

- Los Angeles , CA, USA

This is the second Volt I owned in a year that exhibited this issue. Upon braking and passive deceleration the car makes a loud audible whining noise coming from the engine compartment. The dealer states it is a regenerative brake bearing failure. This issue is related to the bearing cage failing causing the bearing to lose its integrity. GM-Volt.com/forum/showthread.php?17877-loud-whining-during-regen.

- Nashville, TN, USA

I bought a 2013 Volt 2 weeks ago. While at the cvs drive through today the car started to beep warning lights when off, brake pedal went to the floor and the car started moving forward. The brakes completely stopped working, no pumping or anything. I made it into a parking space to await for a tow truck and turned the vehicle off. When I turned the vehicle on the error messages were gone and the brake pedal felt solid again. I started to move the car and the errors came back and brakes failed again. The experience was overall kinda scary. I towed it to the dealer. 2 days later I called the dealer and they informed me that the master cylinder had failed and must be replaced.

- Howell, MI, USA

Antilock feature of brakes will not engage on ice/snow unless brakes are slammed hard. At least three times, I have slid slowly through an attempted stop. It has also occurred twice while gently breaking while traveling downhill. The wheels lock up and vehicle goes into a slide. It continues to happen, but now I know to slam the brake pedal, and the antilock feature will then operate and terminate the skid and stop the vehicle.

- Wausau, WI, USA