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My first Error Code: Fix? post 33 & 38

chl

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Yeah that's the only time the random acceleration has happened to me. If it happens again I most certainly will report it so that it's on record.

This issue could very well end up being the 12v battery I guess. But if so that's pretty terrible. 6 months and 4,400 miles isn't a very good lifespan for a battery, especially when I drive the truck several times each week.
I think you should report the acceleration issue even if it does not come back - it is definitely a safety issue. If you do that and bring it to the attention of Ford as well, if you were unable to stop the next time, at least there would be a record that would prove it was not your negligence that caused the accident.

It is somewhat ironic, but a lot of EVs have a problem with the 12v battery because they rely on so much more electronics I suppose. But you'd think with a HV battery with 98kWhs of energy, some of it could be used to keep the 12v topped off more effectively.

My 2012 Nissan Leaf 12v got depleted when I went on vacation soon after I got it because the charging timers were running, apparently that was enough draw to cause a problem when not driving for a couple weeks. It has been on a trickle charger ever since - still going strong 14 years later.

All 12v batteries will last a lot longer if kept at or near 100% state of charge, something I learned my first year in engineering school, so a trickle charger is a must have in my book. A lot cheaper than a new battery too.

The Lightnings' 12v battery maintaining strategy does not seem to be designed for long life of the 12v battery. Letting these AGM batteries get deeply discharged will shorten their lifespan. Some owners have reported measuring very high charging currents - when a 12v battery is allowed to get deeply discharged, recharging it without current limiting control will result in high currents, which are also not good for longevity.

There seem to be quite a few 12v battery warranty replacements reported here and elsewhere and that's no wonder with this design.

The solution is to keep the battery on a trickle charger with an AGM mode when idle, or plan on replacing the battery frequently. It will keep the AGM topped off without subjecting it to very high currents.
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When hooking up a trickle charger to the Lightning 12v, what is the optimal location? Directly to the battery or somewhere upstream before the 12v BMS?
 

chl

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When hooking up a trickle charger to the Lightning 12v, what is the optimal location? Directly to the battery or somewhere upstream before the 12v BMS?
Negative would be downstream of the 12v BMS...see pic:

Ford F-150 Lightning My first Error Code: Fix? post 33 & 38 where to connect neg for battery charger-info


If you are not downstream of the BMS, the system won't know that you charged the battery.

Also...If replacing the battery, have to recalibrate the BMS:
LVB BMS reset

Make sure 12v battery is fully charged (drive an hour, or after an hour actively charging the HVB)
Start Accessory mode
flash high beams 5 times
step on brake pedal 3 times
red battery icon on dash should flash 3 times

If the dealer changes the 12v battery, they should do this, but they don't always. If they plan on keeping it overnight, there is a good chance they will - Just ask when you pick it up.
 
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So the dealership says the heater assembly has failed. Parts are on order. I hope this isn't a sign of what's to come on this truck.
 

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So the dealership says the heater assembly has failed. Parts are on order. I hope this isn't a sign of what's to come on this truck.
I had a gut suspicion that it or the diverter valve was the culprit, the forum has seen a few reports of either over the years, hope it's not much longer before your riding the Lightning again!
 

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By "heater assembly" I assume she was referring to the electric grid heater portion of the system that's behind the dash? Would that be your assumption too? I asked for specifics but she couldn't really tell me. I wonder exactly how involved this repair is?
 

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By "heater assembly" I assume she was referring to the electric grid heater portion of the system that's behind the dash? Would that be your assumption too? I asked for specifics but she couldn't really tell me. I wonder exactly how involved this repair is?
Lightnings do not have the electric grid heater (like a toaster element) found in older Ford products.

The PTC is an electric immersion heater, a part of the Lightnings original heating system (2022 & 2023).

I believe this component still exists on 2024 & 2025+ Heat Pump equipped trucks, though it's primary duty is to only boost heat requirements to the HVB in cold situations, while the heat pump warms you in the cabin.

Once the repairs are complete, look over the work report, for the parts used in the repair, post a sanitized copy if you can, I'd like to confirm what part they replaced.
 

chl

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Lightnings do not have the electric grid heater (like a toaster element) found in older Ford products.

The PTC is an electric immersion heater, a part of the Lightnings original heating system (2022 & 2023).

I believe this component still exists on 2024 & 2025+ Heat Pump equipped trucks, though it's primary duty is to only boost heat requirements to the HVB in cold situations, while the heat pump warms you in the cabin.

Once the repairs are complete, look over the work report, for the parts used in the repair, post a sanitized copy if you can, I'd like to confirm what part they replaced.
It feels like the "toaster" is now in the heated seat...
 

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What is different about charging a lead acid battery in a Lightning versus any other 12 volt lead acid equipped vehicle?
 

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What is different about charging a lead acid battery in a Lightning versus any other 12 volt lead acid equipped vehicle?
Enclosed space, little to no ventilation.
Think Hindenburg. I myself am dubious, even after looking up how much hydrogen *could* be released, I'm still skeptical, but I also understand the abundance of caution. It's not like the frunk is hermetically sealed, hydrogen is light, opening the frunk is painfully slow, all of these combined makes the only risk an arc in the frunk with an extremely overcharging battery. With the outlet right there, it could happen.
 
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chl

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chl

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According to the people that designed and built your truck the ONLY place you should connect any kind of charger or jump starter is under the passenger side frunk panel.

They put that remote connection point in for safety reasons, hydrogen gas can escape form that 12v battery when charging so you want to stay away from it as far as possible when connecting these items as a spark could set off a reaction that's not conducive to the health of man or machine. See Pic below for proper 12v battery charging connection.

1000014539.webp
Oh boy...unfortunately the designers of the truck put those jumper terminals in a very inconveniently located place where you have to open the frunk and remove a plastic cover every time you want to trickle charge your truck, which should be all the time when not in use for battery longevity...and they are made for attaching clamp-type jumper cables, not made for attaching a standard ring terminal wire.

So yes those are good for jumping another vehicle or your truck in an emergency, but not great for mounting a more convenient easy to access permanent wire for a trickle charger, although a at least one Lightning owner did mount one so he would not have to remove the plastic to trickle charge.
Ford F-150 Lightning My first Error Code: Fix? post 33 & 38 1765654798941-9u



https://www.f150lightningforum.com/forum/threads/charging-12v-battery.16979/post-342839

Yes, don't be stupid and attach the wires with a trickle charger that is live in case your sealed battery has some flammable gas that vented.

Although many trickle chargers nowadays are "spark free," not all are.

And of course don't be careless if you are attaching a ring terminal and nut to the 6mm posts with a metal tool (wrench) so you don't accidentally cause a short!

And use a trickle charging cable with a fuse in case the wire gets damaged somehow.

If you mount an SAE socket like many people have done safely you could use something like this:

https://www.amazon.com/dp/B0BQ3N1N6Z?ref=ppx_yo2ov_dt_b_fed_asin_title

While many Lightning owners have added a convenient trickle charger connection to their trucks without incident, if you are a complete klutz, have your local service station auto mechanic install it...they should be able to handle it.

See all the examples at this forum link:

https://www.f150lightningforum.com/forum/threads/charging-12v-battery.16979/#post-342839

Not rocket science.
 
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Yep, it was in fact the cabin coolant heater, aka the auxiliary heater.

Obviously this was a warranty repair, but if not it looks like it would have cost roughly $1,500. Sigh...

Ford F-150 Lightning My first Error Code: Fix? post 33 & 38 1000020270
 
 







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