Bricked

[YamanoteMaui]

Have been generally happy with my Bolt. The range for the price is decent, its economical, and good for getting around the city. The Bolt is our "leave at airport" car, which we acquired on a 36 month lease. Our state airports provide FREE parking for EVs, which has saved me thousands of dollars in expensive parking fees the past 2 years, so the Bolt earns its lease. I thought there would be some technological improvements over the 36 month lease and like the idea of just putting the car back to the dealer at lease end, no hassles, then get something newer.

The happiness lasted until last week - coming back from a one month absence, I found my Bolt to be completely bricked. The high voltage battery was fully charged, but no response of any kind from the key fob, dash, and the charging light wad extinguished. The car was really a brick - no sign of life, in cold shutdown.

Called the local dealer I leased the car from and there was no hesitation after I explained the issue - tow to the service center.

Then called On Star which immediately dispatched a tow truck, and faster than if I let the local dealer arrange a tow. On Star was great, no issues.

I checked these forums are read a number of postings regarding the 12v low voltage system. Sure enough, I found the 12v battery to be completely dead. Silly me, thinking an electric car would NOT be vulnerable to a dead ICE car battery. This is certainly a design fault or oversight - there is just no way an electric car should brick because a 12 v battery dies.

The tow arrived and I asked the driver to try jumping the Bolt - the jump battery provided enough power to light up the dash and a few basic functions, but unable to operate the car. The Tow driver didn't want to fool with it, so just put the car on a dolly and dragged to dealer service. Thankfully the tow is paid by Chevy, covered.

I will get the car back in a few days, fully ready to go, but now I know I need to keep a trickle charge handy when I am away. That sucks - this is why I wanted a EV to get away from these kind of problems with ICE cars and avoid this type of crappy maintenance issue. After leasing the car, I was hounded by Chevy emails and voice calls asking for feedback on the sales reps, car, and purchase process, hoping to get their NPS score up. However, when I sent emails about this problem to my Chevy rep now, complete radio silence.

Takeaway - seems like a pretty basic design issue. For the price of the car, I would not recommend a Bolt to anyone until the 12v system is rock solid and more serviceable. Buyer should not have to worry about the car being bricked, trickle charging the battery, and 12v system faults. Should never have to worry about a bricked car, for example in an airport lot coming back from a biz trip at 11 PM on a cold winter night......

Perhaps for peace of mind, good idea to carry a lithium jump battery, although I am not sure that would unbrick a Bolt with a fully dead 12v battery.

At the end of the lease, I am certainly putting the car back to the dealer. To anyone considering buying an EV one great question to ask the sales rep is how the 12v low voltage system works, risk of bricking, and dealer warranty in case the car bricks. I will probably look at a Model 3 lease next, as 12v problems seem to rare on Teslas.

 

[theothertom]

I checked these forums are read a number of postings regarding the 12v low voltage system. Sure enough, I found the 12v battery to be completely dead. Silly me, thinking an electric car would NOT be vulnerable to a dead ICE car battery. This is certainly a design fault or oversight - there is just no way an electric car should brick because a 12 v battery dies.

I will probably look at a Model 3 lease next, as 12v problems seem to rare on Teslas.

I hear you but the BMW i3 works the same way. The i3 was generally a slow seller and sat on dealer's lots for a long time, giving the battery time to degrade. Did your car sit on the lot for awhile before it sold? I wouldn't be surprised if the Nissan Leaf and Tesla do the same thing as well, but they tend to sell better than the i3 or the Bolt so maybe not as many opportunities for battery degradation .

 

[iwatson]

Although I guess I understand your issue, a month is a long time to leave any car. The Bolt certainly has the possibility of a work around for your unique situation. The Bolt has the ability to be remote started from an app on your phone. On a long trip as you describe, you could start your car up once or twice a week and let it run for 10-15 minutes, which should keep the 12v system charged.

Once started the car will run for 20 minutes and shut-off automatically, but I'm not suggesting you let it rip until it shuts off automatically. If memory serves you can only initiate two (2) remote starts under this condition. However if you remotely start it, then remotely shut it down after 10-15 minutes, you may be able to get the multiple start ups that your situation requires.

If you decide to test this out, please report your findings, as there may be others that fall into this unique operating condition.

 

[WetEV]

I checked these forums are read a number of postings regarding the 12v low voltage system. Sure enough, I found the 12v battery to be completely dead. Silly me, thinking an electric car would NOT be vulnerable to a dead ICE car battery. This is certainly a design fault or oversight - there is just no way an electric car should brick because a 12 v battery dies.

Designed that way for several reasons.

The HV battery is normally disconnected for safety. The 12V battery powers the circuits and relay that connects the HV battery, and various events would cause the HV battery to be disconnected, such as a crash. Or failure of the 12V electrical system, including the battery.

The battery is a 12V lead acid due to compatibility and temperature range. Everything electrical for a car (headlights, relays, window motors, switches, head unit, brake controllers, etc) is engineered to work with a 12V lead acid battery. A lead acid battery can operate over a wide range of temperatures, wider than the HV battery.

Yet lead acid isn't ideal technology. The working life isn't long, especially at higher temperatures, capacity is lost rapidly if the cell is discharged below 50%, and reliability isn't great. For various reasons, lead acid batteries can die early deaths. As the car didn't jump start, I suspect your battery developed a dead cell. Lead acid cells can fail open or fail short. A shorted cell would prevent the jump start from increasing the voltage past about 10V, and the HV relay circuit probably requires more.

Perhaps for peace of mind, good idea to carry a lithium jump battery, although I am not sure that would unbrick a Bolt with a fully dead 12v battery.

If the battery was just discharged (because of light left on or other power draw), this would work. If you have a battery that failed, it would not work.

I will probably look at a Model 3 lease next, as 12v problems seem to rare on Teslas.

Tesla uses lead acid batteries for the exact same reasons why GM does. Don't expect anything different in this regards.

A bit of searching found this page.

https://syonyk.blogspot.com/2016/10/tesla-model-s-12v-battery-analysis.html

Tesla Model S 12V Battery Analysis
It would be great to be able to start this post talking about how the Model S, much to the amazement of many owners, has a 12V lead acid battery. Sadly, I can't do that - because this battery is a failure-prone sore point among many owners, and far too many owners with a >2 year old car are entirely aware of it, as the battery has already failed and been replaced at least once.

 

[YamanoteMaui]

Thanks, yes, I read that, and some other posts regarding Tesla. I noted lots of bricking issues around 2012, which seem to have been resolved with an OTA software update. The issue noted in the 2016 blog post is around the Model S poor handling of the 12v system, not bricking. I think the Tesla gives a lot of warnings on 12v malfunctions, although I have not experienced. Hard to find serious bricking issues now, but lots of Bolt and Leaf bricks. I'm not a car geek and just want a functional car, that I can depend on and not worry about bricking. The thing about Tesla is they have seemed to perfect the OTA software update process, which seems a MUST HAVE for an EV. Lesson learned.

My bad, have not had a chance to get the recall update done. Would have been great if that could be done OTA, but I gotta have the dealer do it. Super hassle, as I need my car.

I'm not anti-Bolt. I'm pro Bolt. Its a surprisingly good car. Better than any ICE car in a similar class. I get free parking at airports (worth $1000s) and charge from my home solar, so zero operating costs, But the manufacturers have to deal with the 12v problem and remove this worry factor.

When my lease expires next year, its going to be interesting to see what else is in the market. Model 3?, Model Y? Rivian? Kona? Smart? Benz? Volkswagen? eMiniCooper? Real eFiat500? eMoke looks totally cool if they can spec it up to road worthy, but quality is doubtful. My dream is to get an EV version of the Mazda MX-5 Miata. Perfect for an EV!! Second car...... Let see how they all handle low voltage and OTA.

 

[SparkE]

Having a Li-Ion "jump starter" small (size) enough but big (capacity) enough that you can simply connect it to the battery terminals, then *leave it connected* under the hood so that you can drive home and hook your 12V battery up to a charger is ... a very good thing.

Also, regularly trickle charging *any* 12V battery in *any* type of vehicle is a good idea (with the right 'smart' trickle charger). "regularly" can mean twice a month or every two months, depending on driving habits (longer trips, whether in an EV or ICE, charge the 12V better - while short, city trips don't really). I trickle charge the 12V in *every* one of my vehicles at least once a month (unless I drove the ICE for over an hour on the freeway).

But I do tend to put one of my cars on the charger every weekend or two to fully "saturate" charge it overnight, at "less than 1 amp", using a smart charger that is AGM-safe.

 

[paulgipe]

This happened to us in the first week of ownership.

See Our Bolt is Back or How a 12-Volt Battery Can Kill an Electric Car.

Paul

 

[YamanoteMaui]

Read it! Super helpful.

 

[SeanNelson]

Takeaway - seems like a pretty basic design issue. For the price of the car, I would not recommend a Bolt to anyone until the 12v system is rock solid and more serviceable.

I have the suspicion that many of these 12V battery problems are the result of Bolts that have sat on dealer lots for several months without having been touched. If the 12V battery runs down its chemistry is altered and it never fully recovers even after the dealer recharges it for sale. When that happens, the battery is susceptible to dying under the intermittent charging regimen performed by the car's software when it's left alone for a prolonged period.

A Li-Ion battery pack that you can use to jump-start the car is a good idea, IMHO. But don't forget to maintain the battery pack! The Li-Ion jumper pack I bought loses around 20% of its charge after 3 months - so every 3 months I discharge it to verify how much capacity it has and then fully recharge it.

 

[YamanoteMaui]

Bolt is back from service today and the problem was indeed 12V system, i.e., dead 12V battery. Also all recall service done (my bad - should have been done sooner).

For reference, from service ticket: "Multiple low volt codes, GR-8 show bad AGM battery, replaced battery and cleared DTCS"

"Performed gateway reprogram / code 452...... Performed USB radio reprogram as per recall..."

"Performed HPCM2 reprogram as per recall 18097"

No charge for the above.

 

[spazzman90]

LOL regarding the model 3 as a 'better' 12 volt management system.

In short, there is no 12 Volt management system. It is always running, and it uses a lot of power especially in temps lower than 50 degrees ambient. The car would never survive a month parked in cooler temps by itself. It loses 5% per day, just sitting. One of the more annoying aspects of Tesla ownership. Bolt, Spark EV, Kia Soul EV, even Leaf. I can leave sit for a couple weeks and the traction battery doesn't lose anything, and the car is generally ready to go. One more thing. Lose 12 Volts in anything but a Tesla, and you can use your jump pack and go. Lose 12 Volts in your Tesla, and it gets super annoying really quick.

-Jeff

 

[mrdrmorgan]

Although I guess I understand your issue, a month is a long time to leave any car. The Bolt certainly has the possibility of a work around for your unique situation. The Bolt has the ability to be remote started from an app on your phone. On a long trip as you describe, you could start your car up once or twice a week and let it run for 10-15 minutes, which should keep the 12v system charged.

Once started the car will run for 20 minutes and shut-off automatically, but I'm not suggesting you let it rip until it shuts off automatically. If memory serves you can only initiate two (2) remote starts under this condition. However if you remotely start it, then remotely shut it down after 10-15 minutes, you may be able to get the multiple start ups that your situation requires.

If you decide to test this out, please report your findings, as there may be others that fall into this unique operating condition.

This may sound "dumb' BUT, understanding that the 12 volt AGM battery can go dead if the car is parked and not used for long periods of time and no 110 VAC is available for a trickle charger, why not just disconnect the negative battery cable when you leave and reconnect it when you return?

 

[YamanoteMaui]

Yes, silly me, thinking that large high voltage full charged battery was sufficient to keep by Bolt going!

 

[mrdrmorgan]

Yes, silly me, thinking that large high voltage full charged battery was sufficient to keep by Bolt going!

With the ignition turned off and the key FOB removed from the car, I am wondering if the 12-volt battery charging function is also powered down and the HV battery does not charge the 12-volt AGM battery. I say this because whenever I use my AGM 12-volt battery charger, the display shows the 12-volt battery in both of my Spark EVs only have a 50% charge. However, Some functions must remain powered up. Otherwise, the key FOB, Onstar, etc. would not work.

 

[SparkEVPilot]

Yes, silly me, thinking that large high voltage full charged battery was sufficient to keep by Bolt going!

With the ignition turned off and the key FOB removed from the car, I am wondering if the 12-volt battery charging function is also powered down and the HV battery does not charge the 12-volt AGM battery. I say this because whenever I use my AGM 12-volt battery charger, the display shows the 12-volt battery in both of my Spark EVs only have a 50% charge. However, Some functions must remain powered up. Otherwise, the key FOB, Onstar, etc. would not work.

In another post I made on this forum, I reported that the 12 volt AGM battery appears to be trickle-charged when the car is plugged in and, when the car is powered up, the HV battery then provides the main charging of the 12 volt battery.

 

[SparkE]

I read a *very long* post by a GM-certified tech (probably copy-pasted from the service manual) a while back that described the behavior for keeping the 12V battery charged. Basically, if plugged in to an EVSE, the voltage of the 12V battery is checked fairly often (?12 hours?). If not plugged in, it is check every few days (?3 days? 4 days?). And (IMHO) the gateway (limit) voltages are way too low (?12.2V? ?12.4V?). And the 12V battery is also 'checked' and charged while driving the Bolt.

So :

(1) If the Bolt was parked for a long period of time on the dealer lot (or on a train or semi), your 12V battery got hosed and is borderline bad - good enough for day-to-day, but ... in very few days of no use it will go bad. Especially if it was in 'transport mode' and the dealer didn't transition it to 'customer mode' when it was received.

(2) IIRC, the 'battery check' functionality only kicks in if you have >40% main (propulsion) charge.

(3) If you are going to be away for a long period of time and can't leave the car plugged in, pop the hood and unplug the 12V battery. *ALL* modern vehicles (including ICE vehicles) have software running *ALL THE TIME*, which drains the 12V battery so they need to be charged or disconnected during long absences.

(4) I ran into this problem with a friend's LEAF, which was only left parked 4 days - because the 'keep me charged' logic in the older LEAFs was absolutely horrid. This isn't a problem only with the Bolt, and is actually a problem with any modern vehicle (as I already said above). An 'iffy' 12V battery will not stay charged for long periods - I always disconnect the battery in *all* of my vehicles if I am going to be away for more than 7-8 days. (It also thwarts thieves from stealing the car.)

 

[psyflyjohn]

If I was leaving a car unattended for a month at a time, I would have a solar trickle charger inside my windshield. I'd find one that desulphates as well as maintains a small trickle. Upon arrival, the 12v battery would be in better condition than when parked a month ago...