[Dr. Manhattan]

I took delivery of my '17 Volt LT on 3/14/2016...so, an early 2017. The BECM called it a day in late January of this year at between 47k and 48k miles. My dealership ordered the module early February of this year. They finally got one in on 4/25. They also swapped out my leaking oil pan, and I got the car back on 4/29. All is well again...

 

[JP_Solar_Volt]

I took delivery of my '17 Volt LT on 3/14/2016...so, an early 2017. The BECM called it a day in late January of this year at between 47k and 48k miles. My dealership ordered the module early February of this year. They finally got one in on 4/25. They also swapped out my leaking oil pan, and I got the car back on 4/29. All is well again...

Good to hear, I would just love it if they could tell me New BECM - 4-6 weeks.

 

[bareboneii]

Hopefully this isn't a redundant thread but all I could find were threads on 2017 BECM failures.

I'm kind of curious how prevalent 2018 BECM failures are.

Mine occurred at 36,270 miles (300 after BtB warranty expired) and 3 weeks shy of 3 years.

Symptom:
Cruising at 30 mph, engine warning light came on. Battery charge level went from about 60% to 100% charge. Engine started. Shut down car and exited for about 30 minutes.
Upon restart, engine warning indicator remained illuminated (solid, not flashing) and charge indication was normal.
During 20 mile drive to shop, all normal (except engine fault indication).

Finding:
5 fault codes (stored but inactive) indicating BECM. (I didn't get a list of the codes.)
Shop credited the $160 diagnostic fee. Parts available. Be at shop a couple work days.

Questions:
1) The mechanic said that they've seen quite a few BECM failures for all MY gen 2s. Any other 2018 owners out there that have had failed BECMs?
2) Is it normal for a shop to replace (under warranty) an intermittently failed part, or is this just good shop?
3) I assume that the Battery cooling system fluid needs servicing after dropping the battery to replace the BECM. Does anybody know if they would flush it or just burp/service it? Is the BECM on the electronic cooling loop or the battery loop? If the former, same question about flush or service. (Obviously, I would hope for flush so I could zero time those loops.)

Thanks in advance for any feedback. (And moderators, if there are 2018 BECM threads or threads similar to this, please feel free to merge them.)

Regards,
Chris

I just had the dealer say I needed a BECM as my check engine light came on. They are searching for a part but none so far.

 

[snic]

I just had the dealer say I needed a BECM as my check engine light came on. They are searching for a part but none so far.

Which year Volt, and did you report the issue to the NHTSA?

 

[Lhern06]

Update.
Got my Volt back on 05/13/22!
Total time without the car was 04/01/22 to 05/13/22
Everything is great so far!

 

[JP_Solar_Volt]

I just got my '17 volt back after 1 month; about a week after the part came in. My Premier had 65k miles on it when it "blinked". Everything seems normal, range about 45 miles.

 

[Steverino]

Seems like more parts came in in April. Perhaps the supply chain is catching up a bit.

 

[dale.lature]

Thanks CeeW,

I guess we're the only two lucky people (that monitor this site) to have this happen. Maybe that is an indication that it's rare.

I was just getting to the point of not wondering if the car was going to perform properly each time I hit the start button. Now I'm back to thinking about it every day. At least we weren't stranded.

Regards,
Chris

I too have this problem on my 2018, 38k miles. The BECM is on order....3-4 weeks out. That was 9 days ago. Driving normal since, with CE light that goes out after charging. A couple of instances of "unable to Charge", , but able to just a few minutes later. This morning, all of a sudden, trying to shift to Reverse to back out of my garage, "Shift to Park". Will not let me move.

 

[Steverino]

I too have this problem on my 2018, 38k miles. The BECM is on order....3-4 weeks out. That was 9 days ago. Driving normal since, with CE light that goes out after charging. A couple of instances of "unable to Charge", , but able to just a few minutes later. This morning, all of a sudden, trying to shift to Reverse to back out of my garage, "Shift to Park". Will not let me move.

There are a number of YouTube videos on DIY fix for the shifter relay issue. One show bending the contact a bit, or replacing the relay, another has a guy cutting some wires!

 

[FlintHillsSky]

I feel lucky. My 2017 with 49K miles started acting up on Mon 5/23. it was showing multiple error messages including "reduced propulsion" and the fully charged battery showed a 1 mile range. When I tried to put it into gear, it showed the "shift to park" message, which was weird. Doubly so since I had already had that done. Whatever I did it would not move on it's own. At first I thought it might be the 12v battery so I went to Costco and got one. Put it in. Of course that was not the cause. I called the dealer and scheduled a service. I had to call a tow company who flat bedded it to the dealer. Once there, they looked at it a declared that it was the BECM. Ugh, I knew that was bad news. They mentioned having another customer who had been waiting Since mid-April for the part.

They offered to give me a loaner, but when they checked with Enterprise, Enterprise didn't have any cars and was waiting for some to come in. That was doubly funny. Fortunately we have another car and were able to coordinate who used what and when. I was prepared to have to wait it out for weeks.

Then, in the first week of June, the dealer called and said that they were getting some parts in and thought they could get mine fixed. A couple of days later and only a little more than 2 weeks since it failed, it was fixed and I was able to drive it home. I feel lucky that the timing of the fresh supply was just right for my car.

 

[bareboneii]

Which year Volt, and did you report the issue to the NHTSA?

2018 38k miles. Still no part but I was offered a loaner.

 

[KH02]

2018 Volt, 51000 miles, exactly the same problem. Waiting for BECM for 10 days. No estimate when the part will arrive

 

[bobroth4433]

I read this post on Tuesday night and watched the video about the battery. I got up the next morning, got in my 2018 Volt with 42000 miles to go to work. It had 60 miles of range, put it in reverse it moved about 5 ft the range went to zero, the engine started and the check engine light came on all at the same time. I just pulled back in the garage and knew exactly what the problem was, the BECM. After work I was going to take it to the dealer got in it and wouldn’t move. I tried 4 times with the same result it would not move. I called a wrecker to get it towed the next morning. I decided I would try one more time this time it powered right up and I was able to drive it to the dealer, I cancelled the wrecker on the way. It drove completely normal except for that the check engine light was on. I got a call today from the dealer that the BECM needed replaced. Its on back order and was told it might be 2 days could be 3 months. They have no idea when it will come in.

I know it has been a while since you had BECM issues. Do you possibly remember what the outside temps were when the BECM failed, and then when it started working again?

 

[FVolt]

2018 Volt with 68K miles with BECM replacement required. Dealer estimates 30 days to 6 weeks but no firm date on backordered part. Dealer confirmed part of Voltec system covered under 100K warranty,

Was having intermittent issues with "shift to park", followed Youtube solution to remove, clean and replace which seemed to help but with hot weather issue returned and then experienced drive battery charge dropping from full charge to zero and low propelsion power warning and check engine light. Reading blog, I checked 12v battery and found it was reading 12.3v so put on charger to bring up to 12.6 volts and everything went back to normal. After few days (very hot weather) , issues returned and checked battery again had low voltage. Decided to replace battery, since near end of expected life, all was well for week , then new battery voltage dropped to 12.4v so brought in for service diagnostics and dealer identified BECM issue.

Not entirely sure on the BECM functionality but appears like it controls when the 12v battery gets recharged from the drive battery. Since I drive mostly on EV, the ICE alternator charging was infrequent except on long trips.

*Readers who experience this issue and have part order backlog, may want to use a trickle charger nightly and make sure when parking off charger that all electronics are shut off.

 

[MikeBCo]

There is no ICE alternator just a DC to DC converter. It operates differently than a conventional car in how high it charges the 12V battery. BECM is unrelated to charging the 12v battery. It controls the high voltage battery.

 

[phattyduck]

There is no ICE alternator just a DC to DC converter.

Yup, the only 'accessory' on the ICE is the (engine) water pump. Even the hole where the traditional 12V starter would go is blocked off. Power steering, 12V charging, AC compressor, etc. is all electric.

-Charlie

 

[DarkMx-6]

Anyone try to change this out themselves? My dealer had no ETA as to when they can get a battery energy control module and they Want $1800.00 to do it. If I do, do it myself any idea where I can get the module?

 

[TSquare]

Anyone try to change this out themselves? My dealer had no ETA as to when they can get a battery energy control module and they Want $1800.00 to do it. If I do, do it myself any idea where I can get the module?

Just so you are aware, I believe the BECM is INSIDE the 400 pound main battery case. You would need special equipment to disconnect and lower the main battery out of the car. And the module is apparently only available from GM.

 

[Andrew Bohm]

I've been waiting for almost three months for a replacement BECM for my 2018 Volt (22K miles), and the dealership still cannot estimate when the part might become available. I appreciate that supply chain issues have made it difficult for manufacturers, but this is unacceptable. We pretty much stopped driving the car after the problem was diagnosed, but initially it was still driveable - though a few times the battery would cut out and it would revert to an ICE mode and have low power. Now the car just sits in my driveway and gives a "shift to park" error whenever I try to start it up. Do owners have any rights in situations like this? At the very least it seems that GM owes Volt owners some sort of explanation about the delay in getting these parts as well as an estimate as to when they will become available again.

 

[Vpuleo]

Andrew: What is your build date on your 2018 Volt? I have heard it is the early builds that have the problem. My 2018 was built in July 2018 so I am wondering if my Volt will have the same BECM issue?