Accessory battery charging when plugged in?

[flamaest]

Can GM please confirm if the Bolt's 12-volt accessory battery also charges when the the car is plugged in?

 

[flamaest]

Bump.. hello, GM ?

 

[LeftieBiker]

Try measuring the battery voltage at Positive terminal and a Negative ground on the chassis, both while at rest and while charging.

 

[flamaest]

Thank you, yes I will have to do this.

 

[ChevyCustomerCare]

Can GM please confirm if the Bolt's 12-volt accessory battery also charges when the the car is plugged in?

Hi flamaest!

Please know that whenever your Bolt EV is plugged in, the 12V accessory battery is monitored and maintained. I hope this helps to provide some reassurance in this regard!

I do see that you followed up with us via private message, and will be responding to that shortly.

Kindly,

Amber G.
Chevrolet Customer Care

 

[flamaest]

Thank you for the reply.

I used to have an EV before the Bolt which did NOT do this, so I thought I would officially check with GM to be sure.

 

[LeftieBiker]

If you mean the Leaf, they do charge the 12 volt battery while plugged in and charging. What they don't do is charge the accessory battery while plugged in and NOT charging.

 

[SparkE]

If you mean the Leaf, they do charge the 12 volt battery while plugged in and charging. What they don't do is charge the accessory battery while plugged in and NOT charging.

And leaving the LEAF plugged in while not charging can cause a *lot* of traffic to be generated on the CAN bus, which drains electrons from the 12V battery. Just as parking the car in a spot with very 'iffy' cell phone reception, such that the car constantly tries to 'phone home', also pulls electrons from the 12V battery.

Problems with the 12V battery on the LEAF dying after a couple of years - sometimes in just a few months - was an issue (especially the 2013 LEAF).

 

[LeftieBiker]

I had my 2013 SV's battery nearly die (power door locks wouldn't unlock but the fob to button start trick worked) after just a year. I've used a hardwired Battery Tender JR since then, and still have the same battery.

 

[SparkE]

I had my 2013 SV's battery nearly die (power door locks wouldn't unlock but the fob to button start trick worked) after just a year. I've used a hardwired Battery Tender JR since then, and still have the same battery.

I 'babysat' a friend's LEAF these past two weeks while he was away on vacation, and the car wouldn't turn on after sitting for 4 days. So I learned a LOT about this issue in the past week. His battery is shot (he didn't know about this issue either).

How often do you maintenance charge the battery using the Battery Tender? Once a week (overnight)? Once a month? Every night?

 

[LeftieBiker]

I plug in the tender any time I'm going to have it sitting not charging but plugged in, before or after a scheduled charge. If I'll be charging and unplugging it when the charge ends, I don't usually bother. I'd say that for normal use once a week would be the safe minimum, although once a month works for some people. I extended the hardwire cable by two feet, and ran it into the charging compartment, though a small hole I drilled. The maintainer lead runs through the same garage wall hole as the EVSE cable. So using the maintainer isn't hard, but I resent having to do it.