F150 Dead Battery

CKN

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I have been out of the country for the past two months. I asked my son to start the truck. ( Its a 2020, F150- battery can't be too old) but he hasn't apparently started it often enough. And he informs me the truck battery is " dead". I won't be back for another two weeks- so I can't do anything until then. It has been extremely cold as well. Its my understanding it's an AGM battery. Do I assume the battery is too far gone? Or is there an AGM battery charger that would charge it back up? Recommendations on a charger or battery are also appreciated!
 
Just this week I was surprised when I was able to bring the AGM battery in my work car back from 0.2V. Sure, its life has probably been shortened, but it's working fine for now.
 
Any battery charger should suffice. Not sure of Ford's policy, but the Asian imports cover the battery for the full duration of the 3/36K bumper to bumper warranty.
 
Discharged and frozen are not a good combo. Stick a charger on it. The Noco Genius mentioned has an AGM mode.
 
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Any battery charger should suffice. Not sure of Ford's policy, but the Asian imports cover the battery for the full duration of the 3/36K bumper to bumper warranty.
Yes, batteries are 3/36 with Ford. The 94RH7 AGMs have been on and off backorder for the past 2 months. The 48H6 should be readily available.
 
The AGM may come back ok. Saw this happen earlier this year. If you put something small on it, it may take 48 hours or more the fully charge. The small 1 amp and such chargers can recharge a flat battery, but in addition to simply taking a while, they can overheat and shutdown over the prolonged full output; this can lengthen the process.
 
Don't feel bad. I'm babysitting moms 22 Maverick and in a period of 4 days the battery went stone dead here in GA. No idea why, but I charged it and it sat on a Genius 1 for a week or so and it's been fine ever since. No idea why the thing decided to kill it, they're supposed to go into 'deep sleep' if they detect voltage going too low or over 14 days, so in theory the truck should prevent it from happening. Doesn't seem to be the case though.

I was in Forscan a month or so after it happened and the battery information was all set to 'unknown' with no amp-hour capacity set. Don't know if they all came that way or just an oddity of this particular truck, but I set it to contain the correct values and it seems to be fine. Don't really think that could be the cause though since the truck should still have been smarter.
 
I have been out of the country for the past two months. I asked my son to start the truck. ( Its a 2020, F150- battery can't be too old) but he hasn't apparently started it often enough. And he informs me the truck battery is " dead".

You can't just start a modern vehicle, and let it sit there and idle, and expect it to be fully charged.
The vehicle actually needs to be driven to properly recharge a battery.

It probably would have been better off being left alone rather than started and idled for random periods of time.
 
Yes, batteries are 3/36 with Ford. The 94RH7 AGMs have been on and off backorder for the past 2 months. The 48H6 should be readily available.
The battery that is installed to replace the failed one has a unique warranty situation. You do not get the full 3yr warranty on that battery. That battery is covered under the remainder of the term of the NVLW or 1yr/12K miles whichever is greater. The full warranty is no in place because the customer did not financially participate in the repair.
 
You can't just start a modern vehicle, and let it sit there and idle, and expect it to be fully charged.
The vehicle actually needs to be driven to properly recharge a battery.

It probably would have been better off being left alone rather than started and idled for random periods of time.
It would have been better off left alone and with a Battery Tender Jr (or something similar) connected.
 
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Thanks for the replies. I talked with my son today and he said the dome lights would come on- but that's it. Like I mentioned- I will be home in two weeks on a Saturday evening. I intend to order a battery charger on Amazon shipped to my oldest Son's place. Plan on putting the charger on the truck Sunday morning with the battery being good to go on Monday- hopefully!
 
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You can't just start a modern vehicle, and let it sit there and idle, and expect it to be fully charged.
The vehicle actually needs to be driven to properly recharge a battery.

It probably would have been better off being left alone rather than started and idled for random periods of time.
It's not great for it... you get fuel dilution in the oil, and water (vapor) in the exhaust. But it absolutely will charge the battery. Car dealers do this all the time.

Any sort of battery tender (tm) will do a much better job, and cheaper, too.
 
Just how any specific battery is going to respond after a slow depletion to less than 10.5v is dependent on several factors.

The 'dome light only' signifies less than 10.5v, and less than 10.5v for a 12v nomnal battery is considered 100% discharged, as so little energy is stored within once drug below this voltage.

One of the factors is age, and another factor is how the battery ages during its life.

if it was kept relatively cool, and at relatively high states of charge, it has a much better chance of recharging and having enough capacity and cranking amps remaining to provide reliable starting duty service.

But if it were already capacity compromised, then the slow depletion to less than 10.5v could certainly kill it, or ut it right at the edge of reliability.

It, when recharged, and the vehicle daily driven after, could go for another 2 years.
but if the vehicle sits again for a week undriven, its self discharge, AND the parasitic draw of the vehicle itself, can deplete too much of the remaining capacity and all one gets is the click when the key is turned.

A battery depleted below 10.5v, will have many smart chargers just declare a bad battery and not even try to charge it. Some have a force feature.
Fir those without, parallel a good battery with the bad via jumper cables or similar, then start the charger.

A battery depleted below 10.5v behaves a bit weird when a charging source is first applied. It will take very little amperage at first, even if the charger brings it upto 14.5v. If still healthy, the battery will wake up and begin to accept more and more amperage, usually upto the charger's limit, and the voltage will fall back towards 11 or so, then start rising again as the charger is maxed out.

The unhealthy battery might not max out the charger, or only do so for a short period, after it wakes up, if it wakes up.

You might luck out with yout overdepleted 3 year old AGM, after it is charged. You might be OK for another month or 2 and find it dead after sitting for days, or you could be battery shopping come Monday.

There's no telling how it will respond until a charging source is applied. Knowing how much amperage the battery is deciding to accept from the charging source, and at the electrical pressure(voltage) the charger is holding the battery at, can reveal the amount of capacity remaining in the battery, and give clues to its remaining expected lifespan, but few chargers will display the amperage, much less the amp hours delivered during the charging process.

For me, no amperage or voltage displayed on a charging battery, is kind of like driving with no speedometer or odometer, and not knowing where I started, how far I need to go, and no idea how to judge speed at all.

For some others they will just place their trust in the brand of vehicle and a green light to illuminate to tell them when they've most likely arrived.

In your situation, I'd be battery shopping. Formulating options, and hoping they need not be necessary, right now.

An over depleted battery can take far more than 24 hours to recharge fully, though it will likely be enough to get the engine started
The overdischarged battery really needs the true full charge in order to not just degrade at an even faster rate from that point.

While a new healthy battery drained to 10.5v or less, can be fully recharged in about 6.5 hours, with a charger capable of high amperage from that 3% to 85% charged range, ( the last 15 to 20% always takes 3+ hours) and older unhealthy battery can take significantly longer.
both situations assume a higher amp charger which will actually bring and hold the battery to the mid 14v range.

For fear of overcharging the battery, most smart chargers will not hold the higher absorption voltage for the time required to actually achieve a true 100% recharge. The older and more abused the discharged battery, the less likely the smart charger is actually getting the battery near true 100% charged, when it says it is or flashes the green light.

One can often get the battery to higher states of charge with a smart charger, by loading the battery with headlights until voltage falls below 12.6v or so, then restarting charger, then turning off load. It should then hold the battery up in the mid 14's for a period of time before reverting to float voltage or just shutting off. Some smart chargers require unplugging the charger from both AC and DC, then restarting for this trickery to work, and for most people, as long as it starts the vehicle, who cares if it does not get to 100%.

The lead acid battery always wants to be kept cool and as close to 100% charged as possible, for maximum longevity and performance throughout that lifespan. But even if treated perfectly, they will still fail at some point.

An AGM is supposed to have much less self discharge than flooded/maintenance free flooded batteries, but self discharge increases at higher temperatures, and increases with battery age and its declining condition.

As far as any specific vehicle charging the battery when parked, it all depends on what the Voltage Regulator decides to ask of the alternator.

A member here decided to watch the voltage of their F150 closely and found it often decided to basically just send no field current to the alternator's rotor, and make no amperage. The VR would let battery power the vehicle for a period of time in certain situations. An older vehicle might always decide to hold the battery at 14.2v, but a newer vehicle might only bring the battery to 14.0+ in certain situations, like when coasting or braking. Such strategies are intended to increase MPG, and for this strategy to work the battery needs to be kept in the 80% charged range, so that when the VR decides that 14.0v+ is warranted, the battery can actually accept 20+ amps from the alternator. If it were 99% charged it could accept only 2 to 3, and only briefly., and have no chance of gaining that 0.05mpg.

Thinking the vehicles VR is designed for maximum battery life is unwise, in this day and age. The anal retentive, well informed Bitoger wanting maximum battery life needs to bring the battery as close as possible to a true 100% state of charge on a regular basis.

Most will just expect the vehicle to take care of the battery perfectly, and the only variable on battery longevity is the sticker plastered on the side of it.
 
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