Weird battery (maybe?) issue

So...tonight, on my commute home, with 80+ miles left on the range, my Bolt flashes the "propulsion power is reduced" alert and stops letting me drive at freeway speeds ("turtle mode"). I got off the freeway, and watched the range drop from 80 to 50 to zero miles over the course of maybe a mile. I had driven 130 miles since my last full charge at this point.

I call roadside assistance for a tow home, and settle in to wait an hour. Then the tow driver calls me and asks if it'll go into neutral.

I turn it on to find out, and...72 miles of range. But "propulsion power is reduced". And it immediately starts dropping - 60, 50, etc.

Two more hours later (yes, my tow driver got PULLED OVER while taking me home), at home, turn it on to get it into the driveway, and...71 miles of range. "Propulsion power reduced."

So. What's up with that? It seems the battery has a reasonable amount of charge in it, but it doesn't KNOW that it does. It's not really discharged, but it thinks it is?

Anyone have any idea what could cause it? It's being towed to the dealer tomorrow morning, but I'm obviously obsessing over what could cause these symptoms.

This is a known issue, especially with early production Bolts. It seems to be related to either bad cells in the pack or to the battery management system.

LeftieBiker said:

This is a known issue, especially with early production Bolts. It seems to be related to either bad cells in the pack or to the battery management system.

Click to expand...

Really? I know about the battery problem with early Bolts, but this specific set of symptoms isn't what the threads and articles I've read describe. It's also drawing much more charge in "idle" than it was yesterday, and there are a myriad of little software issues. Wouldn't stay connected to CarPlay just before all hell broke loose, forgets the "home" location every time it's started up again tonight (a thing I just discovered).

I believe you, but do you know of any threads that might describe it?

Or maybe I should just go to bed and let the dealership deal with it in the morning.

There is also the possibility that the 12 volt battery is very low, and is causing these odd symptoms. Some Bolts have been left in transport mode and this has caused the accessory batteries to drain. The little lead batteries in EVs seem to be more troublesome than the big lithium packs. I can't steer you to any threads this morning as I'm going to bed. I'm sure the Mods or someone else will be able to do so.

rfrench51773 said:

It's also drawing much more charge in "idle" than it was yesterday, and there are a myriad of little software issues. Wouldn't stay connected to CarPlay just before all hell broke loose, forgets the "home" location every time it's started up again tonight (a thing I just discovered).

Click to expand...

I too think that you may have a bad 12V battery. The symptoms described above sound more like a problem with the 12V system than with the high voltage Lithium battery.

Measure the voltage of your 12V battery with the car off, what does it read? I believe that it should actually be 13V or more, but someone can correct me if I'm wrong.

GetOffYourGas said:

rfrench51773 said:

It's also drawing much more charge in "idle" than it was yesterday, and there are a myriad of little software issues. Wouldn't stay connected to CarPlay just before all hell broke loose, forgets the "home" location every time it's started up again tonight (a thing I just discovered).

Click to expand...

I too think that you may have a bad 12V battery. The symptoms described above sound more like a problem with the 12V system than with the high voltage Lithium battery.

Measure the voltage of your 12V battery with the car off, what does it read? I believe that it should actually be 13V or more, but someone can correct me if I'm wrong.

Click to expand...

The 12v battery would read more than 13v while it's being charged (for instance after startup if the car is not in transport mode) and something over 12.6v when 'idle'. If it is below 12.5 the battery is hurting.

Note that 'Idle' is a tricky word in the case of the Bolt. I interpret 'idle' as zero load or charge on the 12v battery, so main battery conditioning not active, car not plugged into EVSE, no interior lights, etc.

That means when measuring at 'idle' make sure your (1) keyfob is more than 50' away from the car and (2) the car is not plugged into the EVSE. Another key thing to note is that the Bolt uses one of those new-fangled AGM batteries so, if you want to charge your 12v battery, make sure that you have a trickle charger that is AGM capable or you could damage the battery.

The rest voltage that is considered "adequate" for the Leaf is 12.6 volts, with 12.4 still unlikely to cause issues but indicating a low battery. Anything below that and you're in Flake Out territory.

Opening the driver's door on just about any EV 'wakes up' the vehicle (computer wakes, main display comes on, etc.) so if you wish to measure the 12V battery at rest, pop the hood release when you get home, park the car and get out, then wait 15+ minutes before measuring the voltage at the terminals (that way you don't have to open the door to open the hood, and the drain on the 12V battery is minimal).

And, as already stated, keep the keyfob (remote) well away from the vehicle.

After hearing the horror stories from LEAF owners (and having a friend who had to replace the 12V battery on his- they are more expensive than I remember) I bought a very-low-amp, smart, AGM-safe trickle charger that I hook up overnight to my EV every week or three. (And use on my ICE vehicles if they haven't been driven for at least one 20-minute trip in the past month.)

Ugh. Well, I won't find out anything before Monday at the earliest.

But that's because the dealer did nothing at all today.

This morning: "We have a bit of a queue; it'll be end of the day or tomorrow (Saturday). I'll update you tonight."

5:30 p.m., I call them, and the guy says this, "Oh, yeah. It's going to be Monday or Tuesday. We didn't have a Bolt technician here today, and we don't do any diagnostics on Saturdays. So Tuesday, maybe Wednesday."

So, wait, I say. You told me that you had someone to do this today, or else tomorrow morning, and now you're telling me you knew all along that it would sit there all day, AND you say you can't do it until maybe Wednesday. By the way, how did Monday/Tuesday become Tuesday/Wednesday over the course of one sentence?

The guy: "Well, the queue is long, but I'm gonna push to get it done Monday, but if I can't, it might be Tuesday or Wednesday. Plus, you know, we have to figure out if it's under warranty, etc."

Me: The car is six months old. The whole thing is still warrantied. And I'm gonna need a car to get to work next week.

"Well, maybe it's under warranty. And we can't do that. You can come pick it up and bring it back on Tuesday if you want."

Me: and then lose my place in the queue and have it be Friday or Monday of the next week?

Him: "No, no, I'll make sure that doesn't happen. Trust me. I'm a good guy."

So I hung up and called the dealership where I bought the thing, which is farther away. I tell them the story, and they say they will be able to do it Monday, and also they've already reserved a loaner for me for the day, just in case.

Tomorrow I have to go reclaim my car from Sketchy Dealership.

rfrench51773 said:

Tomorrow I have to go reclaim my car from Sketchy Dealership.

Click to expand...

I hope you tell them in no uncertain terms exactly why their service is unacceptable.

SeanNelson said:

rfrench51773 said:

Tomorrow I have to go reclaim my car from Sketchy Dealership.

Click to expand...

I hope you tell them in no uncertain terms exactly why their service is unacceptable.

Click to expand...

Them, and Yelp, yeah, once I've gotten my car out of their hands today.

It'd be okay if the car took a few days to diagnose, if they started working on it when they said they would, and gave me a loaner so that I didn't have to rent a car when clearly the issue is a failure in a six-month-old car. But to tell me they're just gonna get to it next week when they feel like it, and a rental is something I'm gonna have to eat myself. I get that, technically, the warranty doesn't require them to pay for a rental or give me a loaner, but every reputable dealership I've dealt with has done so.

Just for grins measured the voltage on my battery today and it was ~12.62v about an hour after driving (no keyfob or EVSE). It was more than 12.7v when I measured with the car in a similar state two weeks ago, so I thought that was not a good sign.

Hooked up my BatteryMINDer to see what it thought. It went right to desulfate mode and the capacity indicator started on the lower half (2 of 4 LEDs) but quickly went to 3 of 4 LEDs. I thought sulfation was supposed to be around 12.4v, but maybe AGM batteries are different, so it was interesting that the BatteryMINDer felt that it needed to be clean things up on my battery.

Seems idiotic that I have to do this with a one month old vehicle. Gonna check-in with the service guys to see if there have been an firmware changes for the 12v battery maintenance. Doubt they actually know, but I think it's worth giving them some feedback that my battery capacity was dropping.

My hybrid car starts acting wierd every 3 years. Throwing random codes and malfuction lights. The car alarm goes off at random.

Every 3 years I change the under hood 12v battery and the problems go away. (The car is now 14 years old, 225,000 miles, and the NiMH battery works as well as when new.)

In ICE cars I generally had batteries last 5 or 6 years.
I think in hybrids and BEV the 12v batteries fail sooner because there are no starters (no heavy amp loads) and so no heavy amp chargings either. It’s always just a trickle 24/7/365.

I've often wondered why EVs don't use deep-cycle variants of lead batteries. I have one on my boat for lights/bilge pump/etc. It made it through its 8th season just fine with nothing but trickle charge (via small solar panels)/discharge.

I think that it's more about the battery being used quite a bit at lower SoC (60-80% 'full') rather than the heavy charges. I trickle charge my 12V battery overnight regularly (using a *smart* charger) to make sure that it gets a 100% charge. I don't do it EVERY night, but I give it a full saturation charge maybe 1-3 times a month.

GetOffYourGas said:

I've often wondered why EVs don't use deep-cycle variants of lead batteries. I have one on my boat for lights/bilge pump/etc. It made it through its 8th season just fine with nothing but trickle charge (via small solar panels)/discharge.

Click to expand...

Cost. Cheap starting batteries work well enough, so they use those.

This is a re-post from my original back in February. Further investigation I found that there are TWO generations of Bolt Propulsion Batteries. Mine (VIN 41331XX) is A Gen 1 to which the PIM issue pertains to. The cutoff point between Gen1 and Gen 2 packs is VIN: 1G1FXS06H4163254 and they are referred to technically as Vista 1.0 and Vista 2.0 batteries respectively.

Hope that helps.

Well I too had the dreaded "Propulsion Power Limited" message come up on last Dec. 14th.

I was driving locally in Costa Mesa when the message occured. I immediatly pulled over and pushed the OnStar button and was transferred to a assistant who told me that message means the battery is almost out. (It showed 188 mi. range) He then suggested I not shut it off and if possible go directly to the dealer, which I did.

Got the car back 15 days later on the Dec. 29th. Here are the notes from the technician:

**Power Inverter showing wrong voltage causing code P0AF8 Inspect for diagnostic trouble codes
**Found P0AF8 as current.
**Inspect for bulletins. None found for this code
**Using document ID# 4569063 clock in for OLH
**Perform circuit system verification that led me to circuit testing battery main buss line
**Clock out of OLH and call TAC, TAC suggests to continue with document ID# 4569063
**Clock in for OLH. Follow chart to end saying to replace PIM or Battery Relay Block.
**Clock out and call TAC due to parts restriction and order PIM Per TAC replace PIM and program car to WC-1753B and
theft module to WC-XXXXX

Part Number: 24285374

Also had the crappy front seat material re-attached that pulled away for the 2nd time.

Two months later everything has been good except for the driver seat material is once again pulled away!

By the way, my production date was 12/21/16