Deep Sleep Mode - 12v battery drained dead [update: Mach-E jump started]

[GoGoGadgetMachE]

Hope this is resolved and I do not need to have a Battery Tender like the one I have on the Harley I never ride.

maybe it's a chance to ride the Harley more

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[Billyk24]

Makes one think about cutting a couple of circular holes in the cover above the battery for access, then figure out a way to fill the hole with something easily removed. Especially if this is going to be a thing for a while......sounds like removing the two internal covers to get at the 12V battery will get old fast, especially if anywhere other than inside your garage.

Instead of cutting holes can one run a trickle charger wire between the funk panels into the funk so one can quickly attach a trickle charger. Better yet, find a way to route the wire to the front flap so one can do this from the exterior of the vehicle.
Makes me happy not to be an early owner.

 

[kdryden99]

Ive said this quite a few times in other threads, and I got kind of blasted for it. I really believe these EV's do not work well with standard Lead Acid batteries. They need to be AGM. All the electronics in these cars drain the batteries and Lead Acid doesnt hold up well with all these electronics. I might be wrong but I am saying this from personal experience. There no starter, no alternator so the CCA avalable with Lead Acid is not important. What is, is the ability to hold a charge and handle parasitic discharge. AGM batteries do that best.
Tesla had the ssme issues as well and its the reason they switched out all the lead acid and want to convert to Lithium. If there is one thing that I will do if I get the car before this is resolved is ask the dealer to switch to an AGM.
For those who have the car at the dealer checking this issue, Id suggest you do the same.

 

[kdryden99]

Do you mean the 2 wires in the bumper? No, those only open the frunk release, nothing else.

AFAIK the only way to charge the 12V battery (when the car fails to do it itself) is connecting a charger to the battery itself (which is harder to get to) or to these access points (which aren't exactly easy either, since you have to remove the awkward cover). But it's easier than getting to the battery, which is tucked in underneath. The positive terminal is especially tricky to reach.

Thank you, yes thats what I mean.

 

[Billyk24]

And with a brand new 12V battery in there, this is surely a problem that's going to need servicing anyway. This can't be the "normal" condition, even in the very cold. Either the brand new battery is bad, or the car isn't charging it like it should. Either way, it's a warranty service trip.

Damn, Tesla is push production out the door regardless of condition and make new owners return to the service center for repairs and fixing. Better not follow this pathway.

 

[Mopey]

And with a brand new 12V battery in there, this is surely a problem that's going to need servicing anyway. This can't be the "normal" condition, even in the very cold. Either the brand new battery is bad, or the car isn't charging it like it should. Either way, it's a warranty service trip.

You left out an even more likely option. There is a phantom draw on the power. Everyone remember the way Fordpass was\is draining cell phone batteries?

We start frozen ice vehicles at -40+ using 12v batteries throughout the winter. The batteries don't like it, but they work (most of the time.) EVs aren't even trying to turn over an engine where the oil has turned to a thick sludge.

 

[Crilly]

I have had new cars with a bad battery before. I would hope the Mach e has a deep cycle 12v battery.

When mine gets here I well make sure the dealer brings the car inside and charges it to 100%. Both batteries.

If a 12 volt battery is discharged to far and then charged rapidly it well not hold a charge. Turning the car on after it has sat for along time well rapid charge the 12volt battery.

We know they have not sat to long. Right

 

[GoGoGadgetMachE]

I have had new cars with a bad battery before. I would hope the Mach e has a deep cycle 12v battery.

When mine gets here I well make sure the dealer brings the car inside and charges it to 100%. Both batteries.

If a 12 volt battery is discharged to far and then charged rapidly it well not hold a charge. Turning the car on after it has sat for along time well rapid charge the 12volt battery.

We know they have not sat to long. Right

Fun fact: they bought all the 12V when we all did our reservations in 2019! (*)

(*) this is not true

 

[GoosePond08]

I just had my Mach E battery go dead yesterday at only 27°F. I trickle charged it back to life (disconnected the negative cable and attached trickle charger from positive jump port to negative terminal on the battery. After reconnecting the negative lead it started back up.

It's now at the dealer to have diagnostics run on it.

Oh boy. Was check battery on the precheck list?!?!?!

 

[Billyk24]

Hopefully it’s a software issue that can be updated OTA.

Sounds like a Tesla beta fix for a beta fix as a former poster stated in the past.

 

[kdryden99]

Sounds like a Tesla beta fix for a beta fix as a former poster stated in the past.

Some Tesla owners reported an issue where the 12v was not constantly being charged. It is possible that is an OTA fix, but my worry is that the parisitic discharge with the modem and all the electronics is so high the current battery cant handle it.

 

[tomterky]

Ive said this quite a few times in other threads, and I got kind of blasted for it. I really believe these EV's do not work well with standard Lead Acid batteries. They need to be AGM. All the electronics in these cars drain the batteries and Lead Acid doesnt hold up well with all these electronics. I might be wrong but I am saying this from personal experience. There no starter, no alternator so the CCA avalable with Lead Acid is not important. What is, is the ability to hold a charge and handle parasitic discharge. AGM batteries do that best.
Tesla had the ssme issues as well and its the reason they switched out all the lead acid and want to convert to Lithium. If there is one thing that I will do if I get the car before this is resolved is ask the dealer to switch to an AGM.
For those who have the car at the dealer checking this issue, Id suggest you do the same.

This sounds like a great solution for colder climates. Not even owning it for a week and already a dead battery. An AGM may be the answer.

 

[phidauex]

Ive said this quite a few times in other threads, and I got kind of blasted for it. I really believe these EV's do not work well with standard Lead Acid batteries. They need to be AGM. All the electronics in these cars drain the batteries and Lead Acid doesnt hold up well with all these electronics. I might be wrong but I am saying this from personal experience. There no starter, no alternator so the CCA avalable with Lead Acid is not important. What is, is the ability to hold a charge and handle parasitic discharge. AGM batteries do that best.
Tesla had the ssme issues as well and its the reason they switched out all the lead acid and want to convert to Lithium. If there is one thing that I will do if I get the car before this is resolved is ask the dealer to switch to an AGM.
For those who have the car at the dealer checking this issue, Id suggest you do the same.

Unless I'm mistaken, I think the 12V battery is indeed an AGM battery (which is a kind of lead acid battery). Without any access ports I doubt it has fill plugs for a flooded lead acid. If that isn't true, then you are absolutely right, cars like this should have AGM batteries.

Lithium for the 12V battery is tricky because now THAT battery has to be kept warm enough to work. You don't want a battery heater for your starting battery to start the heater for your main battery. I deal with this problem on small UPSs and the like for large solar power facilities.

Lithium Titanate would be an interesting option - not great energy density but they are happy down to -50C, and charge quicker than other lithium chemistries. That is what we use in remote weather stations that have to operate in all conditions (mine is cheerful right now at -9F).

 

[Plutoman15]

Some Tesla owners reported an issue where the 12v was not constantly being charged. It is possible that is an OTA fix, but my worry is that the parisitic discharge with the modem and all the electronics is so high the current battery cant handle it.

Not sure why this is complicated. Maybe I don’t know much but a smart car like this should be able to sense a low voltage in the 12v and use the main battery to recharge it. Even when the car is turned off.

 

[Kamuelaflyer]

I am not telling or going to tell my wife these issues or issues we may have once i get the car (unless it bricks out on us or frequent dealer visits). she wont be ready for all this stuff nor remember any pointers I might have for her. She will have to just use the fob and drive like regular ICE without any feature use.

I'm getting an extra FOB. One for each of us.

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