System off to save battery

[Spiffy]

I put in a h7 battery. I have a Bluetooth battery monitor. I drive and monitor showes charging at 14.9v. As soon as I turn it off if get the system off message. The battery drops to 12.5 voltage..
Is the message coming from the main or aux?

I still don't have interior lights.

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[Puddle]

I’ve got the same problem

 

[Ricksc]

Did you reset the BMS after changing battery?

 

[Scoobtay]

Do the BMS reset pedal dance before you go to bed tonight, and re-assess in the morning

 

[Baz]

I put in a h7 battery. I have a Bluetooth battery monitor. I drive and monitor showes charging at 14.9v. As soon as I turn it off if get the system off message. The battery drops to 12.5 voltage..
Is the message coming from the main or aux?

I still don't have interior lights.

I have never heard anyone say that message is specific to the main battery or aux battery...

After having my main under hood battery replaced under warranty 2-3 months ago, I had my dealer check my AUX battery this past Friday and they did the Rotunda test and it failed. They ordered the AUX battery under warranty and should be here on Wednesday.

 

[staying_tuned]

Mine does this too every so often.

 

[Kodiak]

IMHO when you change the main battery, you may as well change the aux battery. I put in a bigger aux battery but the smaller OEM aux battery is like $70.

 

[Gros Ventre]

Except when in the engine start cycle, the aux and main batteries are paralleled. My inference is that the main battery, if weak or bad, will drag the aux battery down with it. I ended up replacing my main battery at 4 months after delivery (I was on the road) with an off the shelf catalog NAPA Battery. I just swapped it out without BMS reset. On returning home gave the new battery a "wetting down charge." Have not had a peep out of the system since then, 3 years ago and 3 Wyoming winters. In my observation on here, the main battery is the culprit. Swap it out to a non-Ford battery. Temps right now here are around 10ºF in the mornings. There's a lot of talk-talk about the computer setpoint and per cent charge and so on. After I put a voltmeter on my dashboard I observed that the system in long term charging will settle out at 12.8VDC except in the winter when its upward of 14.6VDC. I infer that Ford set the "fully charged" point at 12.8 VDC because an AGM Battery is more susceptible to over charging. Seond the temperature sensor for the system voltage compensation is out in the Pax side mirror assembly leading to higher system voltages in the wintertime.

 

[tbinmd]

interior lights could be out from hitting the switch in the overhead console. I did that once, couldn't figure out why I had no interior lights. Lights won't even come on when you open a door.

 

[Spiffy]

interior lights could be out from hitting the switch in the overhead console. I did that once, couldn't figure out why I had no interior lights. Lights won't even come on when you open a door.

I have covered that. It is not the switch.
When I hit the acc or start the truck with the door open the lights turn on.. they wouldn't if the switch was off. I have blue lights. Switch off they would be orange.

 

[Spiffy]

IMHO when you change the main battery, you may as well change the aux battery. I put in a bigger aux battery but the smaller OEM aux battery is like $70.

I have done that. Replaced both!!!!!!!!!
I am assuming that really no one knows where the system off to save battery cones from. It's frustrating that I got shamed into replacing both batteries. People kept saying try this. We'll 400.00 later I have the same issue.. 330.00 for optimal and 80.00 for aux battery.
Even before I did this i always had a smart charger on the truck. 14.2 volts when I unlock the truck but still no interior lights and I still get the system off nag right after driving and the main battery has been charging at nearly 15 volts..

 

[Hans Moleman]

I have done that. Replaced both!!!!!!!!!
I am assuming that really no one knows where the system off to save battery cones from. It's frustrating that I got shamed into replacing both batteries. People kept saying try this. We'll 400.00 later I have the same issue.. 330.00 for optimal and 80.00 for aux battery.
Even before I did this i always had a smart charger on the truck. 14.2 volts when I unlock the truck but still no interior lights and I still get the system off nag right after driving and the main battery has been charging at nearly 15 volts..

I thought the dealer replaced your batteries? Did you buy another one yourself?

 

[Spiffy]

Yes. I got the dealer to replace the h6. I moved it to another truck. I bought a new h7 . Didn't do anything. I replaced the aux battery even though it tested good. Still didn't do anything.
So I'm out 400.00 without a solution.

 

[Je1279]

You are the first I've heard of where replacing the battery did not solve this issue. Did you fully charge your new battery before installing it in the truck? Also, do you leave any chargers or aftermarket accessories plugged in at all times?

 

[m_bt54]

And did you reset the BMS after replacing with the batteries fully charged?

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