Truck constnatly has 12V low battery warning...

[HammaMan]

Have you tried keeping the HVAC blower on fan speed 5 or higher, continuously? Your voltage issues should vanish just about entirely. I don't drive mine that much, I don't charge the battery ever, and I don't have any issues at all.

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[RyanStroeder]

Have you tried keeping the HVAC blower on fan speed 5 or higher, continuously? Your voltage issues should vanish just about entirely. I don't drive mine that much, I don't charge the battery ever, and I don't have any issues at all.

Yes I've tried doing this - no changes noticeable. thanks so much for all the help so far

Snakebitten: is there a particular bluetooth voltage unit you'd recommend? the plan is to simply monitor the battery for a week or so and take that info to ford?

 

[M.R.F.O.R.D.]

Yes I've tried doing this - no changes noticeable. thanks so much for all the help so far

Snakebitten: is there a particular bluetooth voltage unit you'd recommend? the plan is to simply monitor the battery for a week or so and take that info to ford?

I just bought mine at a Local Princess Auto. Its on clearance. $48.03 Can

12V Bluetooth Battery Monitor

 

[Snakebitten]

Yes I've tried doing this - no changes noticeable. thanks so much for all the help so far

Snakebitten: is there a particular bluetooth voltage unit you'd recommend? the plan is to simply monitor the battery for a week or so and take that info to ford?

A bunch of us are using this one.
(probably the same as the one above)
Search on Amazon for "Battery Monitor BM2 BM3

Should be ~$25

App is in the Apple/Android store

 

[RonOU405]

Mine was doing this as well: low battery message and none of my Ford Pass remote features working. Dealer checked the battery and said it was good, Ford Pass still was not working. Took it back for something else and asked them to check it again. Said the battery was good, but they ran some updates specifically related to the battery and now everything works as it should.

 

[EricR]

Mine was doing this as well: low battery message and none of my Ford Pass remote features working. Dealer checked the battery and said it was good, Ford Pass still was not working. Took it back for something else and asked them to check it again. Said the battery was good, but they ran some updates specifically related to the battery and now everything works as it should.

Please post the service record/receipt from your trip to the dealer.

 

[GrandpaD]

Grrrr...looks like the ol' guy is gonna visit the dealership.

Drove it about 5 miles and decided to hook up a charger. Charger read 12.5v and began to do its thing. About 6 hours later (is a 4 amp charger, getting a 10a tomorrow) charger read 14.7v FULL. I had locked the truck before I started charging and never opened it during the whole process.

Less than 2 hours later Ford Pass sends me an alert that remote functions disabled to preserve battery. I opened the truck to pop the hood...dash flickers then stays dark, 12-inch screen stays dark and overhead lights don't come on. Charger says 12.5V.

Something is seriously draining the battery (or the truck thinks it has).

 

[HammaMan]

Grrrr...looks like the ol' guy is gonna visit the dealership.

Drove it about 5 miles and decided to hook up a charger. Charger read 12.5v and began to do its thing. About 6 hours later (is a 4 amp charger, getting a 10a tomorrow) charger read 14.7v FULL. I had locked the truck before I started charging and never opened it during the whole process.

Less than 2 hours later Ford Pass sends me an alert that remote functions disabled to preserve battery. I opened the truck to pop the hood...dash flickers then stays dark, 12-inch screen stays dark and overhead lights don't come on. Charger says 12.5V.

Something is seriously draining the battery (or the truck thinks it has).

Did you charge so the BMS could read it? My truck w/ the LFP in it doesn't actually look at the voltage or main batt SOC. Based on what I'm seeing it's looking at BOTH batteries. My small LFP dumps electrons into the under-hood AGM until they equalize around 13.3v. Despite being as full as full gets (under-hood batt at 100%), after so many total ah leave the system, the truck will go into low power mode if I do a lot of door opening (powered running boards). The under-hood still will register as 100% but it appears to be tracking energy leaving the aux batt, despite it being able to see loads of current going into it when running. I believe there's a parameter on the Aux batt current transformer monitoring that just makes it think that what it's seeing isn't possible given that the factory 7ah aux batt has 3.5ah worth of usable energy in it.

I'm probably going to just make a 10ga parallel ground run to put the CT on so it can only see a fraction of the aux batt current.

 

[GrandpaD]

Did you charge so the BMS could read it? My truck w/ the LFP in it doesn't actually look at the voltage or main batt SOC. Based on what I'm seeing it's looking at BOTH batteries. My small LFP dumps electrons into the under-hood AGM until they equalize around 13.3v. Despite being as full as full gets (under-hood batt at 100%), after so many total ah leave the system, the truck will go into low power mode if I do a lot of door opening (powered running boards). The under-hood still will register as 100% but it appears to be tracking energy leaving the aux batt, despite it being able to see loads of current going into it when running. I believe there's a parameter on the Aux batt current transformer monitoring that just makes it think that what it's seeing isn't possible given that the factory 7ah aux batt has 3.5ah worth of usable energy in it.

I'm probably going to just make a 10ga parallel ground run to put the CT on so it can only see a fraction of the aux batt current.

Honestly, after your question I'm not following. I attached the charger red to the positive and the negative to the screw above the negative post. Is that correct?

 

[HammaMan]

Honestly, after your question I'm not following. I attached the charger red to the positive and the negative to the screw above the negative post. Is that correct?

Yes, that's correct for BMS monitored charging.

 

[Borchelt]

Agree it likely needs a BMS reset.

 

[GrandpaD]

Yes, that's correct for BMS monitored charging.

Thanks. I learned that from YouTube University.?

But I'm still at a loss as to why (1) voltage dropped from 14.7 to 12.5 in less than 2 hours with the truck locked and alone and (2) with the battery at 12.5 why the truck is shutting down remote access and the dash, 12-inch screen and courtesy lights don't work until I start the truck.

I know zero about electronics but I wonder if there's a correlation between that pop-up "turn off ignition ...saving battery" and something "telling" the truck (i.e. draining the battery) the ignition is on when it isn't.

 

[Chad.Thibodeaux007!]

I was having the same issue with messages popping up in app Remote features disabled to preserve battery even after driving the truck every day. Dealership replaced battery and I have not had any issues since.

 

[RonOU405]

Please post the service record/receipt from your trip to the dealer.

 

[Snakebitten]

I read that TSB as applicable to trucks with the ProPower 2KW variety. ?

I wouldn't think it applies to the Powerboost. Would be interesting to see what codes the technician discovered.

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