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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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For what it’s worth… I just found out today that they now have the part… 7 week wait. I’m selling when it’s fixed. Don’t trust this car anymore. Unfortunate because I really liked it for the first two years
Hello MaryCA
I am a concerned with this BECM issue and trying to gather so background information before it failed.

Year of the car ( in service date)?
mileage ( km / mile ) ?
percentage ( electric/gas)?
type of driving ( % on Highway/city)?
charging ( 120v Level1 / 240v Level 2)?
environment ( parking outside / garage)?
Climate ( state/province)?

Thanks for posting this, it helps everyone who drives a Volt.

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Year of the car ( in service date) Not sure of In service date but it is a 2018
mileage ( km / mile )48000 miles
percentage ( electric/gas) 70% Electric
type of driving ( % on Highway/city) 90% Highway
charging ( 120v Level1 / 240v Level 2) Level2 twice daily
environment ( parking outside / garage) Garage
Climate ( state/province) Eastern PA
Year of the car ( in service date) 2017
mileage ( km / mile ) 84,000 km
percentage ( electric/gas) 57% Electric
type of driving ( % on Highway/city) 75% Highway
charging ( 120v Level1 / 240v Level 2) Level 2
environment ( parking outside / garage)Garage
Climate ( state/province) Southern Ontario Canada
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