[strongworm]

Hey! Need some help, please. I disconnected the main battery disconnect underneath the rear seat and then re-connected it. Car seems to be running fine but I have the little "!"/car icon lit up on my dash. I also received the following e-mail from OnStar:

"A critical issue with the lithium-ion battery in your 2019 Chevrolet Bolt EV has been detected. Please service your vehicle immediately."

I'm assuming that just showed up because I manually disconnected it?

Did this do anything or will the error message go away in a bit?

 

[GJETSON]

Hey! Need some help, please. I disconnected the main battery disconnect underneath the rear seat and then re-connected it. Car seems to be running fine but I have the little "!"/car icon lit up on my dash. I also received the following e-mail from OnStar:

"A critical issue with the lithium-ion battery in your 2019 Chevrolet Bolt EV has been detected. Please service your vehicle immediately."

I'm assuming that just showed up because I manually disconnected it?

Did this do anything or will the error message go away in a bit?

Man! I sweated when I disconnecting the 12 volt battery. What possessed you pull the main disconnect? I looked at mine, out of curiosity, when we first got the car, but never considered actually puling it.

I can't imagine it would actually hurt anything. If it doesn't clear by itself, the dealer can clear it for you.

 

[psyflyjohn]

Sooo... tell us a little more about these desires to play around with the high voltage connects...

 

[strongworm]

No desire to get shocked! I didn't realize what I was doing! I had a few things done on my Bolt last week (cargo false floor installed, black badges, lit charging port) and I heard what sounds like a screw rattling around somewhere. So I was trying to get to the bottom of it and was like, "Oh look, I can pull that out." I thought it was just another battery disconnect, not THE battery disconnect.

Just checked again and it cleared itself... so I think I'm good... *whew*

 

[Pike Bishop]

Hey! Need some help, please. I disconnected the main battery disconnect underneath the rear seat and then re-connected it. Car seems to be running fine but I have the little "!"/car icon lit up on my dash. I also received the following e-mail from OnStar:

"A critical issue with the lithium-ion battery in your 2019 Chevrolet Bolt EV has been detected. Please service your vehicle immediately."

I'm assuming that just showed up because I manually disconnected it?

Did this do anything or will the error message go away in a bit?

Yes, you did trigger a 'crash' sensor. The main battery disconnect is called the MSD (Master Service Disconnect). Lifting the lever with the 12V battery connected makes the control logic think an emergency responder pulled the MSD to remove high voltage from the wiring harness.


Weber Auto covered this indirectly in their 'Battery Disassembly' video.


I had a similar issue when the MSD fuse blew https://www.chevybolt.org/forum/178...bolt-ev-service-disconnect-fuse-bulletin.html



I am surprised it reset itself. But, it sounds like you are back in business and not suffering from 3rd degree electrical burns. (There should be 1/2 the battery voltage present to ground on the receptacle at up to 400A--this is an intriguing level that you should not play with.)

 

[strongworm]

Yes, you did trigger a 'crash' sensor. The main battery disconnect is called the MSD (Master Service Disconnect). Lifting the lever with the 12V battery connected makes the control logic think an emergency responder pulled the MSD to remove high voltage from the wiring harness.


Weber Auto covered this indirectly in their 'Battery Disassembly' video.


I had a similar issue when the MSD fuse blew https://www.chevybolt.org/forum/178...bolt-ev-service-disconnect-fuse-bulletin.html



I am surprised it reset itself. But, it sounds like you are back in business and not suffering from 3rd degree electrical burns. (There should be 1/2 the battery voltage present to ground on the receptacle at up to 400A--this is an intriguing level that you should not play with.)

ICK! I'm usually pretty savvy with this sort of thing, but I'm just having one of those days I guess. So it seems like I exposed myself to a potentially hazardous situation with the remaining 400A?

Looks like things are good but I'm going to charge here in a bit just to make sure nothing else weird happens.

Also, Chevy should put some kind of better warning system on that. It had some pictures but they were worse than an Ikea diagram and nothing that particularly suggested I might burn myself to a crisp.

 

[GJETSON]

(There should be 1/2 the battery voltage present to ground on the receptacle at up to 400A--this is an intriguing level that you should not play with.)

If the car is powered off, the relays at the front of the pack are open. If he pulls the MSD he effectively has two 200 volt packs. The only access to a 200 volt ground is all the way at the other end of the battery.

 

[RichardC]

No one tell strongworm where the one minute self destruct lever is, OK?

 

[jdunmyer]

A while back, I watched the Weber video on the Bolt battery, most interesting! Professor Kelly pointed out that the high voltage battery is "floating", IE, neither pole is grounded. In fact, one of the important steps in reassembly of the pack is to test that no ground exists. IIRC, if a ground does develop, a code will be set, a light on the dash will illuminate, but the car will remain driveable. Also, as was mentioned above, master relays will be open, so you should actually be safe (more or less) even if you should happen to touch the HV connections at the Master Disconnect. I wouldn't test it myself, but....

 

[Warren]

I was just as curious as everyone here. My curiosity was satisfied by watching all of Professor Kelley's videos. He convinced me I do not have the knowledge nor equipment to mess with the electrical system.