12v went bad but gremlins remain

[DrAdamNeal]

Greetings everyone, I am a new Spark EV owner as of July. I am unusual as I live in rural Georgia, so not many Spark EVs around my region (one to be exact). My Spark has 93k miles and I drive it 50 miles per day for commute.

So a couple weeks ago my car started acting a little weird on shut down, it once went to a weird mode where all the lights came on and the drive unit was disabled and it didn't want to turn off. Then a couple days later it turned off and everything went dead it didn't go through its usual shut down procedure and wouldn't turn back on. I was at Walmart when it died so I was able to buy a small 12v battery and put it in and that got me back on the road. I know it is supposed to be AGM so I tried to source the proper ACDelco battery but Oreilly took my money and didn't get it, so I ended up with their closest in store battery which is just a wee bit bigger but I got it to fit. Since putting in the new AGM battery it has driven fine for a few days so I figured that was it. But then this morning dropping off my daughter at school it went flatline when I got back in it to go. I pulled the battery cable off and put it back on and it turned on and drove fine after that. At this point its a minor inconvenience but it worried me since it has a good new AGM in it but still powered down while it was parked for like five minutes.

My question is has anyone else had these issues and is it just gremlins left over from the old battery going wonky or what? I have been wondering if the computer system needs some sort of reset or something. Anyway so far its just bumming me out a bit bc I really love the car and have been putting lots of miles on it but this worries me. I also have to face a lot of scorn for driving an EV in this cultural climate (which is so dumb) and I would hate for the nay sayers to have fuel if my car craps on me. Any advice would be appreciated thanks in advance.

 

[SparkE]

If you do not have a voltmeter , borrow a neighbor's and test the battery voltage AT REST (after sitting for 20 minutes or more). It should be around 12.6V. If not, Charge it with a 12V battery charger.

Also, it is recommended to "trickle charge" the 12V battery - overnight - once a month. It should be a smart charger (one that maintains the correct charge amperage and voltage throughout the charging and then automatically stops charging when the battery is full). Mine is 0.8A max, there are others around 3-4 amps max (and often the max amps are variable: you can set it).

If you charge the battery to "full" and the problems still occur on a regular basis, then something else is going on. You might try disconnecting the negative cable from the 12V and let it sit for an hour before hooking it up again.

If you keep having problems, check the voltage of the battery every morning. If it is lower than 12.5V (more than once) then you may have a vampire drain in your system (something pulling energy when it shouldn't, maybe all the time).

 

[DrAdamNeal]

Thank you very much for the reply. This morning it was dead again even when it was on the charger so I left it and took the family van to work as I am not sure how much it charged and didn't want to fool with it. I do have a smart trickle charger I will have to see if it has an AGM setting on it. I will definitely check the voltage and see what I find. The new battery has only been in it a few days so I would be surprised if it was low voltage but that is a good starting place.

Also, in August we got hit bad by lightning and my car was charging at the time. It was on a grounded outlet and a power strip both of which flipped in the strike (I am only using 110 so far haven't put in a 220 outlet yet). The car was offline after the hit but reinitialized when I opened the door and seemed fine so I didn't worry about it, but the weirdness started after that gradually. Initially it was having a weird memory issue on the miles per kwh avg and would remember wrong after being parked, then it started doing the weird shut down stuff and then the cutting off totally. I have a lightning strike company coming Friday to check our solar system which was also fried in the strike but Idk if they have any way to determine if the car was hurt by the strike.

Thanks again for the reply. I am a long time gear head and forums are the lifeblood of used cars.

 

[SparkE]

Thank you very much for the reply. This morning it was dead again even when it was on the charger so I left it and took the family van to work as I am not sure how much it charged and didn't want to fool with it. I do have a smart trickle charger I will have to see if it has an AGM setting on it. I will definitely check the voltage and see what I find. The new battery has only been in it a few days so I would be surprised if it was low voltage but that is a good starting place.

{...}

When you said "it was dead again even when it was on the charger" , do you mean you were charging the main (propulsion) battery?

It is very important to have an "AGM mode" on your smart charger. AGM batteries generally should not be charged over 14.8 volts. Mine charges at 0.8A until battery reaches 14.4V, then maintains 14.4V while lowering amperage until zero amps, then goes into "maintenance mode" for 10 days (maintains at 13.6V).

Also very important (at this current stage) to test the 12V battery voltage every morning to see WTF is going on. It may be that your DC-to-DC converter (which charges the 12V from the main traction battery) is wonky. The *entire* electric drivetrain has a 8-year & 100,000 miles warranty. If it is the DC-to-DC charger, get it diagnosed AS SOON AS POSSIBLE and it might be fixed under warranty. Do *NOT* mention a lightning strike.

" Thanks again for the reply. I am a long time gear head and forums are the lifeblood of used cars. "

Yeah, I used to play with cars a lot "back in the day". I have rebuilt the engines in a Chevy T3100 ('55) and a VW bug ('65). Once I went EV I never looked back (6 years and going strong). The only things that I have replaced on my SparkEV in 6 years are the wipers, windshield fluid, and 4 tires (winter rains are going in Calif, and the tread on the front tires left on vacation about 6 months ago). Well, I did buy cloth seat covers to keep the seats clean.

 

[DrAdamNeal]

Hello again, thanks for the replies and advice. I think I am just out of the warranty as mine is an early 2014. I had the EV fluid service done recently and it was like pulling teeth to get the dealer to understand what car I had and what I wanted done (granted they didn't sell the SparkEV in GA so I get its unusualness but still). I know I was a little early but wanted to get it out of the way (I think the manual said 97k and I did it at 92k just to be safe).

Part of the problem is that it is so weirdly intermittent. Yesterday morning when I went to get in it the system had shut off again while it was plugged in to the main battery charger, but then last night it didn't shut off and drove fine to work today.

So I checked the 12v battery and from what I can tell the voltage is fine, even when it was shut off and the battery was still attached. I undid the ground cable and charged the 12v with a trickle charger and it was topped off in short order so I don't think it's an issue of the current 12v being bad. In hindsight I wish I had the prior battery checked but I do think it was bad. All the other weird stuff, like remembering the mileage wrong and the wonky all lights on mode has disappeared so I hope all that was a result of the 12v going bad. Now the only issue is this random cutting off while sitting thing. On Monday it did it in the five minutes it took me to drop off my daughter, but then Monday night it almost fully charged than must have cut off in the last 10 percent of charging the drive battery. I did leave the 12v disconnected for a longer time yesterday in hopes that it might signal a deeper reboot of the system but not sure yet if anything is improved unless/until it does it again.

There are still no warning messages or lights coming on and the problem is so randomly intermittent that I really am not sure how to track it. It makes me wonder if there is a fuse that is in the 12v side of the system that could be going bad or a relay or something like that. This is my first EV so I am very hesitant to get into the system unless I really know what I'm doing in there. When I get a chance to poke around I am going to make sure the ground cable connection is solid, as it might have wiggled from me putting in the new battery and if it loosened where it grounds it could cause problems. I have had gassers with a corroded or loose ground wire that had a similar sort of cutting off situation so maybe that's all it is, but I wanted to check with people that knew these cars better first.

Thanks again, I really hope my car is okay as I really love it. It is electric blue and so comfortable for being a tiny efficient car its a pleasure to commute so much in.

 

[DrAdamNeal]

By way of update:

Yesterday the car charged fine overnight and drove fine to and from work. It charged again last night no problem and was happily blinking this morning. So I get in it to turn it on and warm it up while it is still hooked up to charge cable, and it flatlines again when I hit the startup button. I assume it will be rebootable by pulling the 12v cable again but I didn't do that yet because tomorrow a lightning strike company is coming to assess the damages to my home and I want them to see what it's doing. It's a long shot but it was perfect condition before the lightning strike and now it has a weird intermittent gremlin (and no error messages to give any clue as to what's up) so there is some remote possibility that it might be covered by my homeowners if they determine it was damaged (lots of ifs in there...).

So now I wait to see what they say tomorrow and otherwise am still scratching my head. I haven't checked the 12v ground cable yet so when I pull it tomorrow after showing the lightning people I am going to make sure it is good and secure, but other than that I'm not really sure what to do.

 

[JMenacker]

Our 2015 started having a similar issue with the 12v battery losing charge while parked. When we purchased the car new, the dealer replaced the 12V battery - so not sure if the issue was there before and got worse or not. This spring the car only intermittently responded to key fobs, so we replaced the dealer 12v battery with a Delco LN1AGM from Summit Racing. All seemed well after that until a few days ago when DIC and entertainment displays did not turn on.

The car is used as a grocery getter, sitting idle except for short 15-20 mile runs a few times a week. The car stays plugged in to 120v via the original EVSE that came with the car. While HV battery is charging, there seems to be constant 12.8 volts applied to the 12v battery. The 12v discharge is assumed to be occurring after the HV battery charge completes. I haven’t yet tested 12v battery conditions when driving, but plan on getting a cigarette lighter type voltage meter to do so.

We are not sure if a monthly trickle charge is solution. The battery charges fine on the AGM charger setting and holds 12.5 volts for over 24 hours when not connected to the car. However, once connected to the car, the 12v battery seems to have a drawdown occurring (at least when HV charging is complete). More testing is being done today.

Hope your issue is resolved soon. Please post solution if found and I will do same. A good local mechanic said he’d be happy to take a look next week if needed.

Regards,

Joe M in WV

 

[JMenacker]

Trickle Charging the 12v battery disconnected from the car on AGM setting seems to have resolved our issue.

Regards,

Joe M in WV

 

[SparkE]

Sounds like a "vampire draw" on both vehicles. (Power drain that shouldn't be there, sucking energy out if the 12V battery)

OR, it could be that the DC-DC unit (the thing that is supposed to charge the 12V) isn't working properly.

 

[JMenacker]

12v system during testing:
Car off EVSE connected - 14+v (measured at battery terminals)
Car startup EVSE disconnected: 15v initially - drops to around 14v idling (measured at cigarette lighter)
Car driving: settled around 13.1v (measured at cigarette lighter)
Car parked turned off but door not opened: 12.8v initially - drops to around 12.55v after five minutes (measured at cigarette lighter)
Car off EVSE disconnected: 13.4v (measured across battery terminals)

If there is a vampire drain, it is intermittent and not yet identified.

To be safe we ordered a new Diehard AGM H4 battery to keep on hand for a few weeks while verifying the existing AC Delco LN1AGM holds charge successfully. A plug-in volt meter was added to monitor low voltage system when out and about.

Joe M in WV

 

[Porsche]

If you really want to check for parasitic loads, you can get a clamp-on DC ammeter (with bluetooth!) for less than $50.

 

[wywa]

Get a 12v Lithium Ion (preferably LFP) battery and be done with it. Unless you have some particular reason to have that heavy Lead Acid thingy under the hood.
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