Darren Palmer talks Mach-E 12V battery and first OTA software update

[SnBGC]

if you know your car is going to sit for a while, how about you keep 80% in battery and remote start car for a short bit to keep it from completely killing 12v.

not sure why this is such a big issue, the past 20 + years I have had to jump start my car 0 times. I guess I should consider myself lucky, because it seems like some people have to jump start daily with all this concern....

It is my experience a 12v battery will eventually go flat and the vehicle will not start. If you drive the vehicle on a regular basis then your chances of being stranded are minimized but not eliminated. Sometimes the battery gives some warnings....sometimes it's totally fine one day and dead as a door nail the next.

Here in AZ we have a saying......."The battery dies in the summer but we don't find out about it until the winter."

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[SnBGC]

So, EVs are simpler than ICE they said.

Yes, if they have a lock cylinder and a key.

 

[Kamuelaflyer]

I must be missing something here - If the 12V battery is maintained by the HV battery - suppose the HV battery goes dead for whatever reason, then the 12V battery goes dead. Why not just plug the car into a charger? Won't that start charging the HV battery, thus charging the 12V battery?

You have no idea what a can of worms you've opened with that question ...

 

[RonTCat]

Thanks. That explains the issue with pp vehicles then....

So, how does the door latch module receive it's signal to unlatch? It appears the Lincoln system has separate lock and open mechanisms but the language for the MME makes it appear like one module is double acting and it unlocks as well as opens the doors. How does that module know it's okay to open the door if the 12v battery is flat?

Is there enough energy stored in the door latch module to operate the B-pillar controls? If so, then must one use the keypad to unlock and the touch button to open?

(I am assuming the RKE or PAAK is useless with a dead 12v battery......) If that isn't the case then that is truly a remarkable engineering feat.

I don't know the details of the strategy. I've never seen a HV battery go flat where the 12v system was also lost, so I never looked at it. I'm guessing 99.9999% of the people will never use the 12v leads in the front bumper. I guess if you parked your vehicle for 6 months and didn't touch it or do anything to keep the battery charged, you would get the same result as an ICE vehicle, which is a dead battery. For ICE, you use a mechanical key to get in the vehicle and open the hood, and hook up a charger or replace the 12v battery. For Mach-e, you would power the front bumper leads with 12v vs using a mechanical key. Everything else is the same.

 

[VegStang]

My PHEV van went dead when the 12v battery died after the first week I had it, plugging in the HV battery didn't help of course (it was at about 50% anyway.) Using one of those portable, rechargeable battery "jumpers" did the trick. The problem that caused it was related to the onboard charging module (they finally replaced it after 4 trips to the dealer.)

 

[Kamuelaflyer]

I don't know the details of the strategy. I've never seen a HV battery go flat where the 12v system was also lost, so I never looked at it. I'm guessing 99.9999% of the people will never use the 12v leads in the front bumper. I guess if you parked your vehicle for 6 months and didn't touch it or do anything to keep the battery charged, you would get the same result as an ICE vehicle, which is a dead battery. For ICE, you use a mechanical key to get in the vehicle and open the hood, and hook up a charger or replace the 12v battery. For Mach-e, you would power the front bumper leads with 12v vs using a mechanical key. Everything else is the same.

Thanks for the sensible answer Ron. Getting the frunk open so you can jump the 12v, so you can open the door, so you can start the car, so you can use the HVB to drive to the nearest Autozone, so you can replace the 12v battery? Yeah, you've been ignoring warnings for a long time to get to that point.

And the Facebook dog mode guy? That's not happening either.

 

[Raymondjram]

https://www.linkedin.com/posts/darr...rs-discover-activity-6761758714908196864-157I

Ford hybrids do the same operation, where the HV traction battery charges the 12 V battery with a DC-DC converter. The gas engine charges the main HV battery.

 

[Raymondjram]

So, EVs are simpler than ICE they said.

They are mechanically simpler.From the motor to the wheels it uses only three parts.

 

[Raymondjram]

My PHEV van went dead when the 12v battery died after the first week I had it, plugging in the HV battery didn't help of course (it was at about 50% anyway.) Using one of those portable, rechargeable battery "jumpers" did the trick. The problem that caused it was related to the onboard charging module (they finally replaced it after 4 trips to the dealer.)

I know that present hybrids and electrics use the same lead-acid cells that ICES use, so why not use a lithium-ion 12V battery, too? I know that it is more expensive than lead-acid but if you spend over $50k now on an EV, an extra $500 will prevent most 12 V battery failures.

 

[SnBGC]

The part number for the Mach -E's LVB indicates it may be AGM construction.

The question remains.....if the LVB is dead and the modules won't wake up then how does the car validate the owner? I understand the door latch modules are able to store energy for about 72 hours but there still should be some security in that scenario.

After that time.....then whip out the two wires in the bumper....apply 12v and the front compartment lid opens. Then remove the plastic shrouds to access the LVB terminals and apply 12v to wake up the modules so they can validate a key fob or authorized phone is nearby or the keypad sequence is entered correctly. Then pop the doors. I get all that.....no issue there.

It is that in between time.....before 72 hours passes and we are trying to use the energy stored in the door latch module to gain access. Just really curious how does the car validate the owner is the one trying to open the car and not someone else with malicious intent?

And yes, I know about the alarm system and back up battery etc. As far as I can tell, they are separate systems.....but with CAN, nothing is really stand alone anyway so it might just remain a mystery for now....

 

[timbop]

I would have just put a key cylinder in the rear liftgate.

Precisely - they keyfobs all have a blank inside anyway.

The strategy for keeping the 12v system charged with the main HV battery was not finalized until after the pre-prod cars were built.

Honestly, this feels like a case of trying to be too much like Tesla. I can envision the following train of thought:

• Man we need to have a sleek and futuristic look on the car; ordinary keys and door handles are too old fashioned. Tesla uses phones as a key, we should too
• OK, so we'll do that. But we should probably have some kind of a key backup just in case PaaK fails? How about a cylinder and spare key?
• Nah, that's going to be ugly and too old fashioned. We need something fancier. Lets put number pad on the B pillar just like we used to in the old days
• GREAT IDEA! OK, so PaaK and a number pad are the ways to get in
• OK, but just in case shouldn't we have a third option for backup? How about we give them 1 keyfob too.
• YEAH! OK, triple redundancy and no ugly old fashioned low tech junk on the car. It's perfect; nothing can go wrong with triple redundancy!

As for the guy bitching about not getting into a Mach E with a dead LVB doesn't realize Tesla engineered exactly the same single point of failure into their cars.

 

[JamieGeek]

if you know your car is going to sit for a while, how about you keep 80% in battery and remote start car for a short bit to keep it from completely killing 12v.

not sure why this is such a big issue, the past 20 + years I have had to jump start my car 0 times. I guess I should consider myself lucky, because it seems like some people have to jump start daily with all this concern....

No need to remote start it, just setup a preconditioning schedule.

Dead 12V batteries were a frequent occurance on the Focus Electric (happened to mine once).

If you left the Focus Electric plugged in for an extended period of time the 12V battery would go dead as the HVB was fully charged so the car wouldn't "fire up" and charge the HVB and thus the 12V battery would die (mostly due to the car checking into the mothership via the modem).

They did eventually add a "deep sleep" mode to the car where everything would shutdown if left plugged in for more than a few days so the 12V battery wouldn't die as fast.

 

[Badger_Prof]

https://www.linkedin.com/posts/darr...rs-discover-activity-6761758714908196864-157I

With regards to multiple ways to get into the car, please consider that multiple reports from early buyers indicate unreliability for getting into and starting the car with your phone and with the app. Perhaps providing two key fobs would have been prudent.

 

[zhackwyatt]

No need to remote start it, just setup a preconditioning schedule.

Dead 12V batteries were a frequent occurance on the Focus Electric (happened to mine once).

If you left the Focus Electric plugged in for an extended period of time the 12V battery would go dead as the HVB was fully charged so the car wouldn't "fire up" and charge the HVB and thus the 12V battery would die (mostly due to the car checking into the mothership via the modem).

They did eventually add a "deep sleep" mode to the car where everything would shutdown if left plugged in for more than a few days so the 12V battery wouldn't die as fast.

Seems like in the MME, there is no reason to start it or set a preconditioning schedule (for that purpose anyway). It takes care of itself.

 

[ajmartineau]

The part number for the Mach -E's LVB indicates it may be AGM construction.

The question remains.....if the LVB is dead and the modules won't wake up then how does the car validate the owner? I understand the door latch modules are able to store energy for about 72 hours but there still should be some security in that scenario.

After that time.....then whip out the two wires in the bumper....apply 12v and the front compartment lid opens. Then remove the plastic shrouds to access the LVB terminals and apply 12v to wake up the modules so they can validate a key fob or authorized phone is nearby or the keypad sequence is entered correctly. Then pop the doors. I get all that.....no issue there.

It is that in between time.....before 72 hours passes and we are trying to use the energy stored in the door latch module to gain access. Just really curious how does the car validate the owner is the one trying to open the car and not someone else with malicious intent?

And yes, I know about the alarm system and back up battery etc. As far as I can tell, they are separate systems.....but with CAN, nothing is really stand alone anyway so it might just remain a mystery for now....

My question also. When I get mine, I will pop the hood, disconnect the 12v, close it and then try to open the driver's door. Not that ever will need to do this in real life. All the rain up here keeps our batteries topped off.

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