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P0B45 - Circuit/sensor(?) issue in the battery

2646 Views 11 Replies 4 Participants Last post by  jaszy
Drove last night and another MIL came up. P0B45 and P1E00 codes off my BT ODB adapter. Car charges fine. Drives fine.

Dropped it off at the dealer. Had 2 techs (one tech service manager as well) looking at it. Laptop plugged in. They also called GM for assistance. Something about a circuit issue. They'd have to take the T-shape battery off the vehicle and go on from there.

I was given the option to drive the volt (safe to drive) and come back at another time - next Tuesday. Not sure why the delay. Maybe the Volt tech is not in or they are waiting for tools. Either that or take a loaner. Took the loaner instead as a precaution.

Will update this thread as soon as I get more details.
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Discussion Starter · #2 · (Edited)
So I brought the loaner back the day after - left the Volt there. They did not end up taking the battery off the car. I was told to cycle the battery from full charge to zero a couple of times over the weekend and bring it back in so they can further analyze it. On a regular work day, the battery is already depleted by the time I get home (return trip) so it would not be a problem. Anyway, the MIL did not come back. Took it back in today as per their request and they said that everything is operational and that the voltages are fine. They found that one of the battery cells could have accidentally triggered the MIL last week.

I was told by the tech services manager that even if one out of the 192 cells do not produce a voltage to GM's specifications - I don't recall the exact voltage but it was a range - anything over or under, it will throw an error. This was their explanation for the code last week. During the entire process, my dealership was in touch with a Volt Engineer from GM Canada (Oshawa). Case is still open. I will be back in 4 weeks to do another SoC test and diagnosis by the techs. If it a MIL relating to the hybrid battery pops up, then I will be in sooner. Hopefully no problems.

This could be an indication of a failing battery cell. I was told that GM is ready to replace the battery (not sure if it's the entire thing, a portion or just that particular cell) - if and when it does reoccur. Parts will be ready and delivered to the dealership. Everything is documented and GM is aware. Knock on wood, no issues from hereon out.

I just love how GM and my dealership is handling this. I've had terrible experience from another dealership (albeit not Volt-related) and this is a breath of fresh air.
 

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Discussion Starter · #3 · (Edited)
Just got a call from the dealership and they said that I should bring it in next week, Monday. Techs are ready to replace the entire battery pack, as per GM's recommendation. Parts are already in the shop.


:(
 

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Just got a call from the dealership and they said that I should bring it in next week, Monday. Techs are ready to replace the entire battery pack, as per GM's recommendation. Parts are already in the shop.


:(
Sorry to hear that you are having that problem, but glad to hear that GM are doing right by you. If they are really putting as much emphasis on the BOLT and forthcoming EVs it's in their best interest to make damned sure any negative battery issues are mitigated as quickly and painlessly as possible.

Bad press about their EV batteries could really, really hurt them.

Best,
Rick
 

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Discussion Starter · #5 ·
Thanks for your kind works Rick!

Dropped the Volt earlier in the week - Monday. Was given two days ETA. I get a call the following day, Tuesday, that is it ready to go. WOW! They test drove it early in the AM and everything was ok. Charged it a little bit too. GM shipped the new battery overnight via Purolator. Came in a special shipping box/pallet which houses the battery. They told me they are sending the old one back to GM.

So I went to work on a partial charge and then drove home past midnight in the middle of the snow storm. Talk about the ultimate test drive. No changes in driving dynamics. I charged her once I got home. Will do a full 100-0% tonight during my regular commute to see if there is any decrease in range and total kwH used.

But so far, so good!
 

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Thanks for your kind works Rick!

Dropped the Volt earlier in the week - Monday. Was given two days ETA. I get a call the following day, Tuesday, that is it ready to go. WOW! They test drove it early in the AM and everything was ok. Charged it a little bit too. GM shipped the new battery overnight via Purolator. Came in a special shipping box/pallet which houses the battery. They told me they are sending the old one back to GM.

So I went to work on a partial charge and then drove home past midnight in the middle of the snow storm. Talk about the ultimate test drive. No changes in driving dynamics. I charged her once I got home. Will do a full 100-0% tonight during my regular commute to see if there is any decrease in range and total kwH used.

But so far, so good!
Cool (no pun intended). Keep us updated.

Best,
Rick
 

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P0B45 indicates a detected voltage monitoring circuit issue for cell pair 3. Basically the battery energy control module is detecting high resistance in the test CIRCUIT -not really the voltage indicated by the cell or more correctly cells (there's 2 connected in parallel being measured) .
They are obviously replacing the entire battery for simple failure analysis. (Haven't heard of a Gen2 battery needing replacement yet)
Plus it's faster than replacing just battery section #3 where this sensor circuit resides.

I have a bit of a concern however with them permitting you to continue to drive the car , as depending on the vehicle state when/if the fault ever reoccurs it COULD pull the plug on the HV battery (HV contactors OPEN) resulting in a sudden loss of propulsion.

Glad to hear they are fixing you up though
WopOnTour
 

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Discussion Starter · #8 ·
P0B45 indicates a detected voltage monitoring circuit issue for cell pair 3. Basically the battery energy control module is detecting high resistance in the test CIRCUIT -not really the voltage indicated by the cell or more correctly cells (there's 2 connected in parallel being measured) .
They are obviously replacing the entire battery for simple failure analysis. (Haven't heard of a Gen2 battery needing replacement yet)
Plus it's faster than replacing just battery section #3 where this sensor circuit resides.

I have a bit of a concern however with them permitting you to continue to drive the car , as depending on the vehicle state when/if the fault ever reoccurs it COULD pull the plug on the HV battery (HV contactors OPEN) resulting in a sudden loss of propulsion.

Glad to hear they are fixing you up though
WopOnTour
Thanks for your insight, ***.

The original plan was to do some state of charge tests and monitor from there. To see if the MIL would come back. I was scheduled to come back in 4 weeks for said tests but the dealership called to tell me that GM highly suggested to swap a new battery in.

I will post the paperwork here for reference once I get it. Expecting it in the mail as they weren't able to produce it upon pick up of the vehicle. I'll pester them in a couple of days.
 

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Discussion Starter · #9 ·
No issues with the car. Here's the paperwork if anybody is interested. Doesn't specify any part numbers related to the battery though. /shrug

 

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Looks like the issue was intermittent but they replaced the entire battery pack anyways.
Good job by them I figure. In a couple of other similar cases they give the car back only to have the issue appear again at some point.
You should be fine now
Just drive and smile!
WopOnTour
 

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T battery replaced.

I just had the "same" issue without as much detail. The check engine light came on. Onstar said the car threw the high charging code. Dealership checked and swapped out the battery pack - took a week to get the battery pack in. This is for a 2016 Volt that I took delivery on in December and put 2800 miles on. Mostly Los Angeles City/HWY miles and One longish high way trip ~300 miles roundtrip.
 

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Discussion Starter · #12 ·
I just had the "same" issue without as much detail. The check engine light came on. Onstar said the car threw the high charging code. Dealership checked and swapped out the battery pack - took a week to get the battery pack in. This is for a 2016 Volt that I took delivery on in December and put 2800 miles on. Mostly Los Angeles City/HWY miles and One longish high way trip ~300 miles roundtrip.
Sorry to hear that. I also took delivery of said MY2016 in December. I sure hope it was simply a bad batch of battery packs during a given production week and that we are a minority. Ever since the battery swap, I haven't had any problems with the new pack. Charges fine too.
 
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