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2018 Battery Energy Control Module (BECM)

41852 Views 138 Replies 63 Participants Last post by  vap3
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.

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).

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.

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.)

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In the same boat with my BECM after 65k miles. When the failure happened I still was able to drive with the engine. I drove it directly to dealer I bought it from, but dropped that plan when they said no rentals and 7 days to look at. So I drove to work 20 miles away on gas with the dash telling me I had no charge and then full charge, Went to lunch it was dead and had to have it towed from the company parking lot to a different dealer. Rented car down the street. It took 2+ weeks for them to even look at it. And I had to be the one calling them. That is well outside all my GM,Ford, Honda service experience, You have my property on your lot…maybe give me an update on a regular basis? 3+ weeks plus and no promise date. Anyone know where the BECM assembly comes from? I suspect the production line was not longer in place. Are they always providing new BECMs? Can they qualify a “good” BECM from a salvage. GM seems to have miscalculated support for this vehicle. Long term I was worried more about the complex transmission(s) than an electrical control device. If they had a nice big mechanical switch in the back of the Volt where you could convert to 100% gas hybrid it would have been golden for drivers and service departments alike….
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I took delivery of my '17 Volt LT on 3/14/, 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.
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.
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