Opening the door with a dead battery

Kamuelaflyer

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Have I not seen because it’s not listed here or that I just missed any reports than froot was opened with the jumper wires for access to 12V battery under bonnet, 12V battery or external power source applied to 12V system to enable doors to become unlocked, opened etc!
Only if the 12v is totally dead. If it's not "dead enough" the front bumper leads won't release the hood.
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Teslaeata

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Only if the 12v is totally dead. If it's not "dead enough" the front bumper leads won't release the hood.
V many thanks.

If 12V not totally dead, would that enable unlocking of doors?
 

Teslaeata

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No. Those wires only pop the frunk.
Sorry, didn’t make myself entirely clear.

If the 12V battery’s not entirely dead, could the doors still be unlocked and opened before bonnet opened and a 12V slave battery or external power source connected?
 


Teslaeata

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And then, an additional question:

If 12v battery is dead and car cannot be unlocked & opened, is it then possible to trigger the bonnet opener by the jump wires inside tow eye cover, connect an external 12V source to the 12V battery and then unlock and open doors?
 

Pioneer74

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Sorry, didn’t make myself entirely clear.

If the 12V battery’s not entirely dead, could the doors still be unlocked and opened before bonnet opened and a 12V slave battery or external power source connected?
The battery in this situation was in between the level of dead enough to enable the frunk release and too weak to unlock the door. Perfect storm.
 

MoonRiver

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What strands you is when the battery not alive enough to unlock the door, but not dead enough to let you pry its mouth open.

Ford needs to feed the battery better.
 

Ford_orr

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And then if that battery or the transmitter dies?

We all know what the actual most fail safe method would have been…a mechanical key.

But I also assume most of us bought said vehicle knowing that there wasn’t one.
The battery and/or transmitter wouldn't die. The battery would be akin to an Anker power bank you get on Amazon. It would just need to be connected to the LVB just like you connect it to a 120V house outlet. It constantly trickle charges itself to remain at 100% capacity. I've had one of these for almost 10 years and still fires up whenever called upon. The transmitter would have nothing to do with the LVB as it gets its power from the rechargeable battery. If it did fail, it would be an independent failure unrelated to the LVB failure and one helluva coincidence.

As for the mechanical key, I'm with you 100% on that one. Have the key integrated with the FOB, so it slides out when needed. Just one mechanical lock on the driver-side is all that's needed. I'd take that as an option if available in a heartbeat. Just for the piece of mind.
 

Ravensfan1996

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What strands you is when the battery not alive enough to unlock the door, but not dead enough to let you pry its mouth open.

Ford needs to feed the battery better.

I saw a post once about how to get the battery to die by sending a signal to the car over and over and over again to kill it. I wasn’t sure if they did it thru the app or fob.
 

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The battery and/or transmitter wouldn't die.
Obviously it WILL die eventually. Now we can go with arguing lithium batteries are more stable and longer lasting than an AGM. Which it that point….how about they just calibrate the BMS for a 12v lithium and there we go, the door is now also hooked up to a lithium battery.
 

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My understanding that I what is supposed to happen.

The problem is if the door is locked, then it can’t unlock.

Now why some people have seemingly just got out of their car and it locked before they could get the backseat open???
Both my 2021 and my 2024 often lock themselves on me. I disabled walk-away lock on both. I can close the driver’s door and go to the rear driver’s side door and it will lock just as I am pressing the button. Not behavior I would expect. So far, my work-around is to intentionally hit the unlock button before I close the front door. That has worked for each instance where I thought of hitting the button. When I forget to hit the unlock button, the car locks itself on me about 50% of the time. Really crappy and unexpected behavior. 🤷‍♂️🐩
 

zvez

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Folks after almost 4 years of running around happily with my MME, I experienced a LVB failure. My wife managed to drive for 45 min to one of hers hiking trails only to experience the Dead battery issue. The phone rank, her voice a bit concerned that she did something wrong. All was working until she parked the Mach E. I told her that I was on my way with a new battery.
My issue and complaint to Ford is why can’t we all have the way to check the health of our LVB??
Yes….I know, an OBDII reader will be able to help you with the health of the 12V battery. No warning, no notification and no alerts of any impending failure.
It took an hour and a half to gather my tools, a new battery and drive to her hiking spot to change the depleted battery. To my wife, I was a hero. For me was few hours of lost revenue since I took off from work.
Now that this issue is resolved, I wonder if Ford will work on some code to monitor and check the health of that small and pricey AGM battery.
Has to be a way for some of us who can tell when that battery is near the end of its service life.
It feels like rolling the dice every day after the 36 months duration of service life of the battery. Another thing that I learned is that the same battery resides in my Lightning truck. I’m going to have to change the battery in the next 7 months because I don’t want to find out while I am stranded 100-200 miles from home.
Didn't mach lee post in september that ford had announced they were going to give us status indicators in fordpass for lvb?
 

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Didn't mach lee post in september that ford had announced they were going to give us status indicators in fordpass for lvb?
If that is or was the case, it is long overdue. Now that you mentioned it, FordPass didn’t even generate a message of the LVB failure, other than the vehicle was “active “.
 
 





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