BECM starting to fail. Will work and then won-??t work. Having issues intermittently.

- Chicago , IL, USA

The car regularly reports it is healthy and functioning correctly. It is regularly serviced and there was no advance warning of this problem. While driving the car displayed a message to the driver, something such as "reduced propulsion" and the speed of the car was reduced while the internal combustion engine intermittently raced in an uncharacteristic manner. The amber Check Engine light was displayed. A review of error codes later found a communication fault developed with the Battery Energy Control Module (BECM). As soon as it was possible, we got the car to the side of the road and shut it off. We then attempted to start the car and it displayed a warning that no key fob was present (but there was a key fob in the car). A few minutes later the car started and we were able to drive it to a service center where error codes were captured. Afterwards, the car drove as normal, and later even the amber Check Engine light was extinguished. The service center explained this could be an intermittent problem where the car will suddenly throw the error message ("low propulsion") and the car will have to be pulled to the side of the road. It will be a few weeks before the service center can do any work on the car. Since the car may start and drive, but suddenly find its speed reduced to far below the speed limit, the car can no longer be safely operated.

- Olympia, WA, USA

The battery energy control module failed mid drive causing my car to come to a stop in the middle of traffic. The car was towed to a dealership mechanic shop where the BECM had indeed failed. There was no signal that is was going to fail it just simply stopped and as it stopped the check engine light came

- Wichita, KS, USA

While driving to work, the vehicle shook a bit and entered into "reduced propulsion mode". The vehicle had a significant reduction in engine power on the road (the propulsion became very jerky), which became dangerous on the highway. There were no previous indicators of any type of issue. After brining the vehicle to the dealership, I was told it would be okay to drive until my appointment (which was scheduled for the subsequent week). Two days later, the vehicle would not start. When attempting to start the car, the "Shift to Park" message displayed. I had to get the vehicle towed to the dealership at that point. The dealership mentioned it is likely an issue with the Battery Energy Control Module (BECM). However, I'm still waiting for a resolution.

- Sparta, NJ, USA

On 2 separate time periods, "propulsion power reduced" message appears on dash: - 1st incident in November 2022, car would not move after powering off the vehicle. After sitting idle for a week, decided to retry, and car seemed to work normally. Took it in to Chevy service, they replaced the BECM. Car worked fine after this - 2nd incident in November 2023, again 'propulsion power reduced' message appeared. This time, however, car would suddenly cut off gas engine (even at highway speed), switching to 100% battery mode, and displaying 'Engine not available' on dashboard. Fuel level indicator would immediately display 'LOW' (even though gas tank was full). Reduced acceleration on battery mode. Car is now in same service center awaiting fix for the past month. Was quite an unsafe situation, especially at highway speeds, and especially given the fact that the battery also may have been at a low state of charge, risking complete vehicle breakdown. Coupled with both of these incidents, the cruise control intermittently shuts off, displaying 'Cruise control unavailable'. Car is lightly utilized, with just over 30k miles on the odometer to date. Additionally, the car is kept in a mild climate (coastal southern california) and parked in a covered spot shielded from sun and temperature extremes.

- Venice, CA, USA

Battery Energy Control Module failed resulting in significantly reduced and unreliable propulsion power available reducing maneuverability and increasing risk of collision at speeds over 45 mph. Check Engine Light illuminated as well as a -??propulsion power reduced-?? message on the dashboard. The problem was confirmed by a dealer and repaired under 8 year / 100000 mile voltec warranty.

- Kailua, HI, USA

The gm repair started the "vehicle power control module" - gm (24296765) is bad. Cause the car to stop, and not restart, 12v won't charge. dealership states the part on back order over 60 days, not expecting it any time soon.

- Texas City, TX, USA

The EGR valve failed, causing the loss of propulsion message on July 11 2022. This was fixed, however the message was received again in December 2022.

- Perrysburg, OH, USA

I was driving on the freeway and the engine turned off. I was able to continue driving as the hybrid system still had some charge to continue powering the car. I had to get the EGR valve replaced. No warning lights prior to this occuring but had check engine light after. Car would not shift into drive nor would it accept a charge for the main drive battery. Had to be towed to a shop and resulted in getting the Battery Energy Control Module (BECM) replaced.

- Huntington Beach, CA, USA

The car started stating "put in park" every time I would try to put the car in drive. I would shift back and forth from park to drive over and over and I could get it to clear. One time it lost all power and had zero control. Sat on the side of the road for an hour. Shifting back and forth until it stopped and let me engage the drive. The last time it happened in a parking lot and it would just say"shift to park" I couldn't get it out of park. Had to have the car towed. Tow driver had to drag the car on the flat bed with a wench because it was stuck in park. Had the vehicle repaired. Replaced an electronic control module that had previous service bulletins on but GM would not cover the repairs. I was lucky I was not injured our involved in a wreck when I experienced these issues. I was not aware I could file a report about this until I read there was an open investigation on the same issue I had.

- Crestline, OH, USA

1. 2 BECM failures: The original BECM failed and the replacement BECM failed as well. 2. Sudden loss of electric propulsion on the freeway while my wife (pregnant at the time), my son (1 year and a half) and I were driving. The car was still driving but was unstable when steering and with weak braking. The dealership identified the issue as BECM failure and the part was changed. 3. A couple of months later the car would not start at all leaving me stranded at work. The car was towed to the repair shop. The dealership diagnosed BECM failure again. 4. There was no warning indication or message prior to these issues. 5. The vehicle was only inspected by the dealership to the best of my knowledge.

- San Diego, CA, USA

Started acceleration on the freeway, car couldn't turn on engine, message came on dash "reduced propulsion mode" and check engine light came on, could only drive on battery, car was very sluggish, luckily had battery to exit after a few miles to get off the freeway. Had to restart car. If I had depleted the battery as I usually do that day, I would have had a dead car on the freeway with ton of traffic buzzing me and my family.

- Barnum, MN, USA

My Volt will suddenly lose propulsion. The air conditioner will stop working and the car will not properly accelerate. There has also been multiple occasion where the car will not power on. Additionally, there has been multiple occasions where the car won-??t charge. The failed component is most likely the battery engine control module. My safety and that of others is at risk because of the sudden loss of power and inability to maintain highway speeds. The issue was confirmed at the dealer. The check engine light goes on even after erasing codes, and there are 13 permanent codes related to this issue with no direct resolution. This is a recurring problem.

- Mount Dora, FL, USA

Sometimes when the vehicle powers on, it will not engage to drive in gas or electric mode when fully charged or with a full gas tank. Also sometimes while driving, it will say "gas mode not available propulsion limited". It frequently says "charging not available" as well. This is an on going, intermittent, problem.

- Saint Cloud , FL, USA

Car intermittantly lost propultion while driving. this started happening more and more frequently. One time driving on the freeway propulsion cut out and I barely made it to the side of the road. Put the car in park and it would start again. Drive for a few hundred feet then it would cut out again. Finally took it into the dealer when I was driving down the highway and propulsion cut out and I was stuck in the middle of traffic. As I was driving the instrument cluster power remained on but the engine just cut out. I was using the electric motor at the time but this is happened on the ice as well. As I rolled to a stop in the middle of traffic I put it in park so that I could restart the car as I had been able to previously but it would not start. It would not let me shift the car out of park into neutral so I could push it to the side of the road. After several attempts of disconnecting the battery and the high voltage battery I was able to get the car out of park into neutral. Even when I shifted the car into drive the propulsion system would not work, a officer stopped traffic to allow me to push the car to the side of the road. After getting to the dealer they were able to determine that a ground strap to the engine chassis was at fault. It interrupted the communication on the can bus which wouldn't allow the ECU to communicate with the drivetrain Which just shut down the propulsion system. This was extremely scary I have attached a snapshot of fault codes and snapshots of a video I took showing that the screen would just show that the car was initializing the entire time

- Ogden, UT, USA

On Nov5th 2023 the dash displayed "Shift to Park" and "Unable to Charge" and would not move. New 12v battery installed on the 7th, still had issue. OBD codes pointed to MAF and MAP sensors. Both replaced, but now "Reduced power" displayed on dash and erratic and limited to 30 mph driving function was experienced. PRND shifter replaced and car worked fine for 1 week. Then "shift to park" and difficulty to move car was happening again. Called dealer and under "reduced power" drove car to dealer on Nov 22nd. Car was erratic and I felt like it would stop moving at any time while in traffic.Now dealer has has car and they say they are not sure of solution and parts may take weeks to arrive. Saw article in Reuters about other Volt owners with same problem on Dec 1st, so I'm adding my car to the group. Thanks!

- Buffalo, NY, USA

The check engine light came on in my car with the message "service charging system." I took the car to the deal and they determined it was the battery control module that was failing. They told me the car would eventually stop turning on and I could either take it and drive it until it wouldn't turn on or I could leave it with them until they got a replacement part that is currently on backorder with no estimated time they can get it. I asked if the car was safe to drive and if it would stop working while I was driving, they assured me it would not stop while I was driving. I opted to take the car home and on my home, while driving, the car died on me. Luckily I was already in a turn lane and was able to get off in a neighborhood. The car gave me a message "propulsion system unavailable" while I was driving and would not power the car forward or backwards. This happened about six weeks ago and I am still waiting for the replacement part.

- Rochester, MN, USA

In the last couple months, have received multiple warnings regarding reduced propulsion that, as I understand is a potential failure related to the BECM. Besides the warning, I haven-??t noticed any major change in performance, but I am concerned there may be a defect. I haven-??t yet contacted dealer about this issue, but I noticed there was a formal report made about this and wanted to be sure my vehicle was included in the count.

- Lancaster, PA, USA

The EGR Valve has failed and they have not provided a replacement yet. Been 4 months. Decline to give an ETA.

- Longview, TX, USA

Cart fails to start nearly every time I try to start it. BECM failure seems to be the issue. Car instructs to shift to park then fails to start until eventually it clicks over and will start in gas mode. Sometimes will randomly flag into low propulsion mode while driving, which majorly affects acceleration speed. Car will no longer charge and must be used in gas mode due to known electrical defects. Sometimes have to wait 10+ minutes for the car to start.

- Pontiac, MI, USA