12v battery problem can have serious consequences

[dtbaker61]

Mine was plugged into the provided Ford Mobile Charger, outside in -40C, into 120v
The manual for the mobile charger says it good to -30C
I woke up in the morning to the charge fault, and the car was flat dead in the driveway, last time I drove it was the previous morning.

I just installed a Grizzl-E in my garage to not get caught again

very interesting....

I would hazard a guess that at -40C, the battery warmer could not pull enough juice via 120v (x12amps = 1200-1400 watts thruput) outlet to keep the battery core temp above 0C. If battery internal temp hits 0C I would bet that the charger (in the car) sends a fault to stop charge. Not really a fault with the mobile charger, just a limitation of charging with 120v x 12a versus 240v x 32a

It is BAD to charge lithium if cell temp is below 0C

I would hazard a guess that if you were plugged into 240v 50a outlet, and MME could pull 32amps, it might have been able to keep warm AND charge. So, I dunno if you need a Grizzl-e, but you DO probably need a 240v outlet.

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[Shayne]

Mine was plugged into the provided Ford Mobile Charger, outside in -40C, into 120v
The manual for the mobile charger says it good to -30C
I woke up in the morning to the charge fault, and the car was flat dead in the driveway, last time I drove it was the previous morning.

I just installed a Grizzl-E in my garage to not get caught again

So a charging fault also Mach-e dead again. So do you think the car should be smart enough to negotiate a charger and not drain its 12V battery overnight? If the charger goes down that is no reason for the mme to drain its 12V overnight (few hours). What type of phantom drain do you need for it to do that? The charger is not the smart one or pushing the MME to drain its 12V. Something in the MME is triggering it.

 

[Shayne]

very interesting....

I would hazard a guess that at -40C, the battery warmer could not pull enough juice via 120v (x12amps = 1200-1400 watts thruput) outlet to keep the battery core temp above 0C. If battery internal temp hits 0C I would bet that the charger (in the car) sends a fault to stop charge. Not really a fault with the mobile charger, just a limitation of charging with 120v x 12a versus 240v x 32a

It is BAD to charge lithium if cell temp is below 0C

I would hazard a guess that if you were plugged into 240v 50a outlet, and MME could pull 32amps, it might have been able to keep warm AND charge. So, I dunno if you need a Grizzl-e, but you DO probably need a 240v outlet.

I understand not bad but dangerous as you create a time bomb charging frozen batteries. Impact will set it off. They can freeze with no health loss but you need to warm them up before charging them. I have seen mine at -11C; below 0C many times. When they thaw out I understand they will be as good as new.

40 amp Grizzl-e extreme does not help. Charger was still steady green when the charging fault occurred. Nothing wrong with the charger to date. Bit hard for me to start pointing at a dumb charger made it do it. That would be a hard line to sell. It is the MME's 12V that is dying nothing to do with keeping the HV battery warm and I do not think you need to and hence departure times. Reduced capacity but no harm.

 

[dtbaker61]

I understand not bad but dangerous as you create a time bomb charging frozen batteries. Impact will set it off. They can freeze with no health loss but you need to warm them up before charging them. I have seen mine at -11C; below 0C many times. When they thaw out I understand they will be as good as new.

correct, you can USE frozen lithium batteries.... which actually helps warm them up internally. It's just bad for the batteries to attempt to add charge when the core temp is <0C.

40 amp Grizzl-e extreme does not help. Charger was still steady green when the charging fault occurred. Nothing wrong with the charger to date. Bit hard for me to start pointing at a dumb charger made it do it. That would be a hard line to sell. It is the MME's 12V that is dying nothing to do with keeping the HV battery warm and I do not think you need to and hence departure times. Reduced capacity but no harm.

If the HV core temp goes <0C, the MME will not permit charge to protect the lithium

using a 120v outlet likely doesn't permit enough juice to warm HV to above 0C and charge. The OP mentioned they were charging via 120v pigtail on the mobile charger....

if HV<15% SOC, the LVB and car is 'off' it won't get charged no matter what you are charging with, the HV has to be above 15% before it will wake up and maintain LVB.


so if you are trying to charge in a place <0C, you really should be charging on 240v
if your HV is <15%, you can keep the LVB up by leaving the MME 'on', and not timed out.

 

[YFD_233]

I am sad that the U.S. is still the only nation using the obsolete Imperial System from the old U.K. and many citizens will not learn the Internstionsl Metric System. As an EE I learned the Metric System in 1970 and use it more than the Imperial System. It is extremely easy to learn as there are just three units: meter, liter, and gram. And Celsius is related to water, so O C is ice and 100 C is steam.

If you need to ask, I am a New Yorker, and more American than anyone else here. That is why I am sad.

They’re too busy teaching critical race theory.

 

[Shayne]

correct, you can USE frozen lithium batteries.... which actually helps warm them up internally. It's just bad for the batteries to attempt to add charge when the core temp is <0C.


If the HV core temp goes <0C, the MME will not permit charge to protect the lithium

using a 120v outlet likely doesn't permit enough juice to warm HV to above 0C and charge. The OP mentioned they were charging via 120v pigtail on the mobile charger....

if HV<15% SOC, the LVB and car is 'off' it won't get charged no matter what you are charging with, the HV has to be above 15% before it will wake up and maintain LVB.


so if you are trying to charge in a place <0C, you really should be charging on 240v
if your HV is <15%, you can keep the LVB up by leaving the MME 'on', and not timed out.

When I could not set a charging schedule I ran 120V to take it longer to get to 100%. It worked OK but that was -15C range. I can see it stressing at -30C to add to the HV but not killing the cars 12V. Where is less than 15% soc on the HV here? I am not running it down that low in these temps. Still getting use of it.

 

[Dhruval Shah]

here in Quebec we have been experiencing a wave of polar cold for a few days. We reached temperatures of less than 30 Celsius. Several Mustang Mach-E owners have had issues with the 12v battery. One of the people who had this problem was put in a situation that would have serious consequences as she described in her post on the FB site « propriétaires Mustang Mach-E Quebec ».
''A really worrying situation happened to me with my MME premium AWD this morning: I had 115km of autonomy and after a few stops during my shopping my car did not start and I heard a noise in the speakers . I called roadside assistance and there was a 1:30-2:30 wait so someone came to pick me up because I was with my 10 month old baby in the car. After 20 minutes when I got out of the car the door closed behind me and the doors wouldn't open anymore and my baby was stuck in the car for another 30 minutes while the police and the the tug arrives. The tug wasn't able to open the door as it's all electric and there is no emergency way to open the doors if the battery is dead...had to have my dealer move on place and he opens the hood with an intrumejt and dismantles plastic parts to access the battery so that the doors open and I can get my baby out. Words fail me to tell you how my mom's heart suffered during this episode and that I really don't want it to happen again…. After reflection I want to know if this happened to another of you? And here are my solutions and I especially want to hear yours. My car is at the dealership for diagnostics. I would like to be able to have confidence in my vehicle and I will need them to be very convincing for me to agree to take it back…
- change of battery for a more powerful one?
- added smart charger?
- display the level of the 12 volt battery and an alert if it drops below a critical threshold
- Make a reminder for doors that do not have an emergency opening system

Thanks for helping me think through all this….’’
I hope Ford will fix this problem once and for all….
Ps Sorry for m’y english

Hi did you find any solution for the same? I'm from Manitoba,Canada and my car died thrice in this weather. My dealership gave up telling me to keep it plugged. Last time i kept it unplugged for 20 mins and it died. I dont know how to deal with it now.

 

[Mosworthy]

very interesting....

I would hazard a guess that at -40C, the battery warmer could not pull enough juice via 120v (x12amps = 1200-1400 watts thruput) outlet to keep the battery core temp above 0C. If battery internal temp hits 0C I would bet that the charger (in the car) sends a fault to stop charge. Not really a fault with the mobile charger, just a limitation of charging with 120v x 12a versus 240v x 32a

It is BAD to charge lithium if cell temp is below 0C

I would hazard a guess that if you were plugged into 240v 50a outlet, and MME could pull 32amps, it might have been able to keep warm AND charge. So, I dunno if you need a Grizzl-e, but you DO probably need a 240v outlet.

Dunno
I was planning on buying something anyways
But it is in the manual that the provided mobile charger is good to only -30°C

 

[Shayne]

Dunno
I was planning on buying something anyways
But it is in the manual that the provided mobile charger is good to only -30°C

It will be hard to find one that certifies colder but you can certainly find one that is more robust. They all seem to state certified to -30C but that is not a wall just a certification it will function prefect until then and not a statement that it does not work if colder. A better HV charger will not keep a 12V from draining.

 

[Budman]

An interesting piece of info from another thread that could explain some of the recent 12v LVB issues? It refers to an issue where an instrument panel light can stay on and drain the battery.

https://www.macheforum.com/site/thr...ith-ota-ford-power-up-2-1-0.13232/post-333154

 

[Griddlez]

Has anyone ever investigated hiding one of these on the exterior of your car? Like in the wheel well or near the (what would be) hitch area? I think this could pop the hood and then provide some charge to the 12v battery to get the car started again?

https://www.amazon.com/NOCO-GB40-Ul...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

 

[Hey_Moe]

I have had the same messages twice on my MME with the last stretch of cold weather. It isn't the coldest that it has been in Northern Minnesota, and I hadn't had any issues with it starting at -20F or colder up until recently. The first time it gave me trouble it was -11F and this morning it was a balmy 3F. When it gave me all of the warnings and wouldn't pop in drive the first time, I just left it and walked home (not too far!). By the time I had my husband over to boost the battery it had been sitting in the sun (still cold out, though) for a couple of hours and fired right up as usual without doing anything. I suspected that some sensor was frosted over which eventually cleared off sitting in the sun.
This morning I had the same dash messages after leaving it parked in the cold. The car wouldn't go at all, and I decided to just crank up the defrost (my windshield was frosty on the inside from being in our warm garage before I parked in the cold). I left it to sit and get nice and toasty for about 10 minutes or so and tried again. It did start and let me drive home, but the warning messages were still cycling through. I'm thinking those are fake news and after it's plugged in in a warm garage they'll disappear. I really love this car and hope that this is a bug that we can work out!

 

[dtbaker61]

I have had the same messages twice on my MME with the last stretch of cold weather. It isn't the coldest that it has been in Northern Minnesota, and I hadn't had any issues with it starting at -20F or colder up until recently. The first time it gave me trouble it was -11F and this morning it was a balmy 3F. When it gave me all of the warnings and wouldn't pop in drive the first time, I just left it and walked home (not too far!). By the time I had my husband over to boost the battery it had been sitting in the sun (still cold out, though) for a couple of hours and fired right up as usual without doing anything. I suspected that some sensor was frosted over which eventually cleared off sitting in the sun.
This morning I had the same dash messages after leaving it parked in the cold. The car wouldn't go at all, and I decided to just crank up the defrost (my windshield was frosty on the inside from being in our warm garage before I parked in the cold). I left it to sit and get nice and toasty for about 10 minutes or so and tried again. It did start and let me drive home, but the warning messages were still cycling through. I'm thinking those are fake news and after it's plugged in in a warm garage they'll disappear. I really love this car and hope that this is a bug that we can work out!

total bummer.
I'd try pulling the driver's side beauty cover, and stuffing a 12v electric blanket all around the 12v battery, and connecting to the handy dandy nearby connection points. Yes, it will draw on the LVB, but the MME should 'wake up' periodically and charge the 12v from the HV.

 

[mkhuffman]

total bummer.
I'd try pulling the driver's side beauty cover, and stuffing a 12v electric blanket all around the 12v battery, and connecting to the handy dandy nearby connection points. Yes, it will draw on the LVB, but the MME should 'wake up' periodically and charge the 12v from the HV.

I don't think this will work. I connected a bluetooth OBDII reader and it drained my battery down to 10% before I plugged it in and it recovered.

I was monitoring the LVB to see what would happen, and it seems that when the car is plugged in, it charges the LVB when it gets down to 40%. When it is not plugged in, it looks like it did a small charge at 10% but it really didn't do much of anything until I plugged it in.

So if you leave your car unplugged outside in the cold for a long time, I can see how the 12V could be damaged over time. However, I did notice that when the car is unplugged, it goes into a deep sleep (as most everyone knows) and unless you have something draining the battery (like my OBDII scanner), it should last for a long time unplugged.

It seems to me that people experiencing low LVB must have a problem with the car, assuming there isn't anything draining the battery like I did in my test (such as a heating blanket. ;-)).

 

[JimmyMachE]

Excellent test. What is your 12V standby drain average (quiescent) after obd2 dongle was connected so long? And normally without obd2 dongle connected overnight?

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