Battery for Frunk Release to store in bumper

[louibluey]

I was thinking the same thing. I thought the process was apply power to the small door in the front to get enough power to open the car and then pull (twice) the hood release.

That would actually make more sense (applying the boost battery through the little bumper door). In fact, assuming the LVB is not dead-shorted, it takes so little energy to start a MME, you could probably just start the car that way.

Instead, the red and black wires of this thread are only used to be able to electrically pop the frunk latch (as an alternative to the double pull mechanical release in the cabin), so that you can first open the frunk, then remove the two plastic sheets (back and side) to get access to the regular EV +12V and GND jump points, to try to jump the car!

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[Kandiru]

I keep the main unit on my center console plugged into the 12v outlet, the rest in trunk with car specific tools (nosecone removal wedge) . So far it helped start a small sedan and Toyota Tundra at my workplace parking lot these past two winters. Chickened out and had the 12V battery replaced after five years at my own cost. As others said, make sure you know where the quick access battery posts are and have the right tools in the trunk to gain access.

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[generaltso]

I keep this on my center console plugged into the 12v outlet. I started a small sedan and Toyota Tundra at my workplace parking lot so far. Chickened out and had the 12V battery replaced after five years at my own cost. As others said, make sure you know where the quick access battery posts are and have the right tools in the trunk to gain access.

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Having that in the car won’t help if the battery’s dead because you won’t be able to get into the car.

 

[TheVirtualTim]

My plan is to just phone the auto-club.

 

[SnBGC]

Where is the Front Trunk Release Relay? with its connector C2435?

Found the Aux relay box, near the firewall, windshield.

Here is the Latch connector C1846:

 

[kdryden99]

Why not use a capacitor instead like this

https://www.ebay.ca/itm/13-5V12F-13...42a89c6a87752c0718b1|ampid:PL_CLK|clp:2334524

 

[GoGoGadgetMachE]

Oh my gosh YES!
It would have been sooooo much easier and better to just put a lock cylinder in the liftgate and some 12v terminal blocks back there.

lock cylinders do and will rust if left long enough without being used. it happened on my '95 Mustang GT and a friend literally shattered the window while screwing around in the door trying to release it. Ended up having to have the lock mechanism and the window replaced.

Do any of the Ford power liftgates have lock cylinders? how does that work?

seems between the power liftgate on the back and the fancy door power stuff on the passenger doors, the only place you could have a properly working key latch at all is the frunk, and then where would you put it? hide it behind the horse or something?

 

[SnBGC]

lock cylinders do and will rust if left long enough without being used. it happened on my '95 Mustang GT and a friend literally shattered the window while screwing around in the door trying to release it. Ended up having to have the lock mechanism and the window replaced.

Do any of the Ford power liftgates have lock cylinders? how does that work?

seems between the power liftgate on the back and the fancy door power stuff on the passenger doors, the only place you could have a properly working key latch at all is the frunk, and then where would you put it? hide it behind the horse or something?

That would be fine. The Continental hides its lock behind the emblem on the drivers door.

 

[buffasnow]

Do any of the Ford power liftgates have lock cylinders? how does that work?

seems between the power liftgate on the back and the fancy door power stuff on the passenger doors, the only place you could have a properly working key latch at all is the frunk, and then where would you put it? hide it behind the horse or something?

Behind the charging door would work too, as someone recently mentioned. Side benefit of that location would be some measure of weather protection, also being front of mind enough (from plugging in regularly) to lube/test the lock cylinder from time to time.

 

[GoGoGadgetMachE]

Behind the charging door would work too, as someone recently mentioned. Side benefit of that location would be some measure of weather protection, also being front of mind enough (from plugging in regularly) to lube/test the lock cylinder from time to time.

Nobody (*) would ever test it until the needed it and then it would be potentially too late.

(*) yes yes I know this is when everybody on here says they test and lubricate all their car locks constantly including taking the emergency key out and moving the little covers (trunk and both front doors) just in case their power locks don't work (**)

(**) "no you have it wrong, this will be the first car I have ever owned with key fobs and power locks"

 

[kdryden99]

Another option is removing the latch all together and installing hood pins instead
https://www.ecstuning.com/b-aerocatch-parts/aerocatch-top-mount-locking-sr/120-2100/

 

[louibluey]

Another option is removing the latch all together and installing hood pins instead
https://www.ecstuning.com/b-aerocatch-parts/aerocatch-top-mount-locking-sr/120-2100/

With the LVB related software updates and warm weather, I think the scenario of getting totally locked out is becoming less likely. The solution for now is easy enough, just pack something 12V into the bumper port, maybe in a plastic bag with some padding. The 12V battery from first post, the smaller one later in the thread, a loaded 12V AA battery holder (with wires or contacts), a very small boost pack, just about anything like that should work to pop the frunk lock in this worst case scenario.

If I get some time, and finally past these recent 20F windy days, with the new diagrams, I will continue to explore a bit, just for some electronics fun/curiosity. I am sure there are a lot of MME electronics enthusiasts (including ham radio, still a few around ), technicians, engineers, etc. who enjoy these sorts of projects (technical nerd/geek fun).

FORD - READ THIS - The indicated 12V LVB connection in that first diagram is probably just symbolic for put a 12V battery here when needed (or a drafting mistake). There is not a direct wired connection from the red wire ring lug to the +12V post as shown in that first drawing. Maybe when this is sorted out a bit more, Ford could correct that drawing, or add a note explaining the LVB next to the connection points.

I'm guessing that double relay module might be an interlock, so that the release latch (the actual coil at the latch) gets locked out, to prevent electrical release, such as while driving (just a guess at this point).

The direct access to the latch coil might make for an easy measurement of resistance and/or inductance to shed some light on the latch part itself.

Finally as noticed by a few, pulling F72 should give some easy electrical access to experiment with frunk opening by battery or power supply to see what it takes to get it open in this (hopefully) less likely (preferably unlikely) situation.

 

[SnBGC]

With the LVB related software updates and warm weather, I think the scenario of getting totally locked out is becoming less likely. The solution for now is easy enough, just pack something 12V into the bumper port, maybe in a plastic bag with some padding. The 12V battery from first post, the smaller one later in the thread, a loaded 12V AA battery holder (with wires or contacts), a very small boost pack, just about anything like that should work to pop the frunk lock in this worst case scenario.

If I get some time, and finally past these recent 20F windy days, with the new diagrams, I will continue to explore a bit, just for some electronics fun/curiosity.

FORD - READ THIS - The indicated 12V LVB connection in that first diagram is probably just symbolic for put a 12V battery here when needed (or a drafting mistake). There is not direct wired connection from the red wire ring lug to the +12V post as shown in that first drawing. Maybe when this is sorted out a bit more, Ford could correct that drawing, or add a note explaining the LVB next to the connection points.

I'm guessing that double relay module might be an interlock, so that the release latch (the actual coil at the latch) gets locked out, to prevent electrical release, such as while driving (just a guess at this point).

The direct access to the latch coil might make for an easy measurement of resistance and/or inductance to shed some light on the latch part itself.

Finally as noticed by a few, pulling F72 should give some easy electrical access to experiment with frunk opening by battery or power supply to see what it takes to get it open in this (hopefully) now less likely situation.

Agree. That diagram needs a revision. The location links are clickable and it says it is located under the hood when it should say "external auxiliary battery" or something similar.

 

[CHeil402]

With the LVB related software updates and warm weather, I think the scenario of getting totally locked out is becoming less likely. The solution for now is easy enough, just pack something 12V into the bumper port, maybe in a plastic bag with some padding. The 12V battery from first post, the smaller one later in the thread, a loaded 12V AA battery holder (with wires or contacts), a very small boost pack, just about anything like that should work to pop the frunk lock in this worst case scenario.

If I get some time, and finally past these recent 20F windy days, with the new diagrams, I will continue to explore a bit, just for some electronics fun/curiosity. I am sure there are a lot of MME electronics enthusiasts, technicians, engineers, etc. who enjoy these sorts of projects (technical nerd/geek fun).

FORD - READ THIS - The indicated 12V LVB connection in that first diagram is probably just symbolic for put a 12V battery here when needed (or a drafting mistake). There is not a direct wired connection from the red wire ring lug to the +12V post as shown in that first drawing. Maybe when this is sorted out a bit more, Ford could correct that drawing, or add a note explaining the LVB next to the connection points.

I'm guessing that double relay module might be an interlock, so that the release latch (the actual coil at the latch) gets locked out, to prevent electrical release, such as while driving (just a guess at this point).

The direct access to the latch coil might make for an easy measurement of resistance and/or inductance to shed some light on the latch part itself.

Finally as noticed by a few, pulling F72 should give some easy electrical access to experiment with frunk opening by battery or power supply to see what it takes to get it open in this (hopefully) less likely (preferably unlikely) situation.

One important test would be to see what the current draw to pop the hood is. I think it is very likely that some AA batteries in a 12 V pack should suffice. Especially if you use lithium AA batteries they can supply up to 2 A without alarming degradation...

(Source: https://www.powerstream.com/AA-tests.htm)

UPDATE 3/25: Confirmed that 9V battery doesn't work. https://www.macheforum.com/site/thr...ease-9v-battery-does-not-work-12v-works.4774/ And 8 AA batteries do work! https://www.macheforum.com/site/thr...tery-does-not-work-12v-works.4774/post-141023

 

[GoGoGadgetMachE]

One important test would be to see what the current draw to pop the hood is. I think it is very likely that some AA batteries in a 12 V pack should suffice. Especially if you use lithium AA batteries they can supply up to 2 A without alarming degradation...
(Source: https://www.powerstream.com/AA-tests.htm)

I'm currently working off the a pair of assumptions - one, that with the software fixes, as some others have said, this is not going to be the issue it was two months ago, and two, that even if it does come up again, it won't be at the level it has come up in the past - so say "I have to do this more than once in a short period of time" won't be as big a deal.

Time will tell if those assumptions are accurate.

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