I was driving on the freeway at 65 miles per hour. As I began to brake because of traffic, 3 lights came on the vehicle. Stabilitrak failure, ABS and brake assist failure. When the lights came on, there was a loss of breaking. I almost crashed. Had I been closer to the vehicles, I would have had an accident. Fortunately, I keep a distance from the vehicles in front of me at all times. I called General Motors and they told me to take it to the dealer and they would look at the repairs and find out if it is something that is related to the vehicle's safety. When I took it to the dealer, I received an estimate fro M jackie, the technician at mark christopher auto center 2131 E convention center way, Ontario, ca 91764. Stated that there is two separate issues with the vehicle. One issue was the stabilitrak and the second issue had to do with the ABS. Each of the items were estimated differently even though they were related. I ended up coughing up $290 for just an inspection of both items (not repairing them). 160 was for the check engine, stabilitrak and brake assist falure. The second charge was to look at the ABS at $130. I disputed the charges but they stated that they were valid. When I spoke to the technician ( jackie) she stated that the car was repaired and the problem stemmed debree going in to the I told them that I had a case # with GM. Jackie stated that GM would not honor the repair because it was the speed sensor. She stated that the sensor was cleaned and the vehicle does not have the problem anymore. It is difficult to understand that such a simple fix does not have a re-call. This is a safety sensitive issue that has implications for society as a whole. Imagine a person driving and they do not know the system is malfunctioning. This can be harmful to pedestrians walking in the streets. The system does not allow you to brake. Please help!!!!!!!

- Fontana, CA, USA

On Wednesday, December 13, 2017, I was backing up from a starbucks parking lot when I hit my brakes hard to avoid another car (also backing up). The car was in reverse gear at the time I applied the brakes full force. Fortunately, we did not hit each other and I drove on and exited the parking lot. At the first intersection I noticed my brake and stabilitrack warning-indicator lights came on. I was on a surface street with light traffic and when I attempted to brake, as I did, the car swerved and would not brake properly nor come to a full stop even when the brake pedal was fully depressed. Pumping the break I was able to manage with intermittent braking ability and drive the car to my home (which is only a short distance from the starbucks). I opened the hood to check the brake fluid reservoir and saw that it was almost completely empty. I could see fluid dripping and pooling under the engine of the car. I contacted the Chevrolet dealership and towed the car to them for servicing the next morning. At the dealership, I explained what happened to the service manager and filed a report on GM's online reporting system. The manager came back after inspecting the car and told me that there was extensive damage to the braking system but could not give me a complete assessment other than the master cylinder and brake line would need to be replaced. The car was repaired according to the work order but after testing they found that the problem persisted. I was told that the brake pressure moderator value needed to be replaced. 14-days from the time I towed the car in the final repairs were completed.

- Westlake Village, CA, USA

I suddenly totally lost braking power at a stop sign. Was at about 30mph when I tried to apply brakes. I cross the street at good speed and car finally stops about 100 meters away. Display messages: Regenerative braking disable, service your brakes, service stabilitrack. Warning light: ABS, stabilitrack and maybe others. I then drive this car very slowly in this condition for 5 km. The brake pedal was up and very firm. At home, I shot off car and plug it. One hour later, it was back in perfectly normal condition, no warning light and no message. Test drive show good brakes. I bring the car to the dealer on Monday. They found one hidden to customer (no check engine) code, C12E6. They follow instruction and replace ABS module. They told me that if I get same problem again they will replace ABS pump. I argue with no luck that I cannot go away driving a car with possible sudden brake lost issue. I then contacted GM (Volt advisor) with no better results. GM apparently study my case for 3 months. After that, advisor call me and ask if I have lost brakes again. She said since you haven't lost brakes for 3 months, we consider your car to be well fix, case is close. I personnaly believe that the code is not related to the total brake lost. An ABS module can not shut off brakes. The electric brake booster may have a design flaw. Nissan had similar problem with the leaf at low temperature, they made a safety recall. Volt and leaf have similar electric brake booster. Temperature was 18 deg F, road was covered with packed snow, traction was fair. I was getting the usual low traction message when applying brakes too hard before the total brake lost event. Volt brake system involve computer in order to blend regenerative braking and friction brakes. The brake booster is electric (no vacum) and computer driven. I happen to be the actual brake engineer for ski-doo snowmobiles!!!

- Sherbrooke, Canada, VT, USA

While backing up at low speed, my wife applied the brakes and the pedal went to the floor, she lifted her foot and applied the brakes and once again the pedal went to the floor. The car did not slow or stop. The speed was so low that the car came to a stop on its own when there was a small rise. The indicator light said "low traction". this occurred in a private parking lot. The car was backing straight with no steering.

- Sacramento, CA, USA

Warning lights for brakes, ABS, and stability control system illuminated on start up and backing out of the vehicle from a parking space. The brakes were mushy but would still stop the car but with much greater effort. The Volt apparently has a mechanical fail safe braking mechanism (other than the parking brake) in the braking system even if the hydraulic pressure fails. Contact with on star indicated a dtc of C1121 - left front hydraulic system leaking. There was no external evidence of brake fluid leaking on the vehicle and the master cylinder reservoir was at the maximum level. The vehicle was repaired by replacing the master cylinder since the brake pressure could not be maintained over 159 psig. While recognizing that any vehicle part can fail at anytime, failure of a brake master cylinder at such low mileage should be rare. This submission was only to help identify if the master cylinder in the 2014 Volt is failing at more than normal rates.

- Cedar Park, TX, USA

Incident occurred while coming to a stop at a traffic signal on city streets. Reached approximately 5 mph as I approached he intersection, when brake pedal went to floor, and normal braking failed. Pressing the pedal as hard as I could, was able to get car to a stop in 2 car lengths, but overran the limit line. Luckily there were no pedestrians or other vehicles in front of me. No injuries or property damage. Car was towed to dealership for diagnostics. Car reported "leaking brake circuit" via remote manufacturer diagnostics. Internal displays indicate "brake assist failure", "ABS failure" and "stabilitrak service required".

- Concord, CA, USA