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Old Jun 26, 2025 | 12:13 PM
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Power grid question

My Godzilla has two alternators and two batteries. Do they feed the same power grid, such that if the truck was running and you disconnected one battery, the two alternators and other battery would power everything to keep it running? I can't imagine that one alternator and battery are dedicated to like lights and fans and stuff like that, while the other pair is dedicated to processors and displays and such.

I've seen threads where "keep the battery at 95%" and other percentage centric comments are made. Where in the menus and screens do you find the percentage? I can only find voltage level.

All this is leading up to the idea of disconnecting the battery(ies) to reboot whatever is making my folding mirrors not work. If both batteries are disconnected to make sure all power is absolutely off, how long do you do that for? Does it wipe memories, like map favorites, radio stations, HUD settings, etc?
 
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Old Jun 26, 2025 | 12:20 PM
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There is no built-in percentage readout that I am aware of. The truck does report voltage, and percent of charge is usually an approximation based on the resting voltage reading between 10.5 (0%) and 13 (100%) vdc.

Both batteries are connected in parallel, meaning their capacities are added together in a 12v bank.

To clear the BCM in an attempt to fix things like mirrors and door locks not behaving themselves, disconnect the negative terminal on both batteries for 10-15 minutes.
 
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Old Jun 26, 2025 | 01:08 PM
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Thanks Tsax6010. I was wondering if the percent was another feature I couldn't find. So disconnecting doesn't wipe all my personalized settings? I've never reset my "Trip 2" data because I want the fuel economy average since day 1. I would feel bad if I lost that.
 
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Old Jun 26, 2025 | 01:09 PM
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Originally Posted by F250 Platzilla
Thanks Tsax6010. I was wondering if the percent was another feature I couldn't find. So disconnecting doesn't wipe all my personalized settings? I've never reset my "Trip 2" data because I want the fuel economy average since day 1. I would feel bad if I lost that.
Things like trip setting will remain but the transmission will start over relearning. Which isn't a bad thing actually.
 
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Old Jun 26, 2025 | 02:32 PM
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I thought I remember reading that on trucks with dual alternators, that the second alternator is normally in-active until the truck sees enough electrical load to require it.

I have the dual batteries/alternators on mine too. I cannot figure out how someone would manage to pull ~400A of 12V to require that much alternator.
 
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Old Jun 26, 2025 | 06:48 PM
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Originally Posted by Stugots5170
I thought I remember reading that on trucks with dual alternators, that the second alternator is normally in-active until the truck sees enough electrical load to require it.

I have the dual batteries/alternators on mine too. I cannot figure out how someone would manage to pull ~400A of 12V to require that much alternator.
A large inverter or DC to DC charger. A 3000w inverter at 85% efficiency can draw 250A alone.
 
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Old Jun 26, 2025 | 07:01 PM
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Your 2nd alternator is separate from the rest of the system, dedicated to the power inverter. It outputs 24 volts.
 
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Old Jun 26, 2025 | 07:22 PM
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Originally Posted by seijirou
Your 2nd alternator is separate from the rest of the system, dedicated to the power inverter. It outputs 24 volts.
That is true only if the OP's truck has the optional 2kW Pro Power Onboard. The OP did not mention anything about having this option. If not, then the included dual alternator system on the Platinum is a 250a and 160a alternators.
 
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Old Jun 26, 2025 | 09:47 PM
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Originally Posted by shawnee1
That is true only if the OP's truck has the optional 2kW Pro Power Onboard. The OP did not mention anything about having this option. If not, then the included dual alternator system on the Platinum is a 250a and 160a alternators.
Indeed. When I built my 24 it wasn't possible to un-select the pro power on the platinum, but I see that changed for 25.
 
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Old Jun 26, 2025 | 10:45 PM
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Correct, the 2kW was an option, like $950, which i didn't buy. I figured I would buy a portable generator if I needed power in a remote location. I have used the 400W outlet for running my PC and recently running my oscillating saw at our cabin. That day, we were all set up to paint some doors, and the utility power went off. D'oh! Had to run to Home Depot, a 2.5 hour trip, to buy a 6500W gas/LP generator for $830. And the power came back on about 10 minutes after we returned. Oh well, it can power the cabin or our travel trailer.
 
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Old Jun 29, 2025 | 08:36 PM
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Originally Posted by Stugots5170
I thought I remember reading that on trucks with dual alternators, that the second alternator is normally in-active until the truck sees enough electrical load to require it.

I have the dual batteries/alternators on mine too. I cannot figure out how someone would manage to pull ~400A of 12V to require that much alternator.
That's what I was thinking. Having two alternators would be easier on each one for those pulling high amps, and Ford wouldn't have as many warranty claims on the large scale.

For me, I don't have high electrical draw, so I'm sure one would be fine, but having two would probably last longer before you need an alternator replacement. Even if one fails, then the other will kick in. Would you even get a check engine light if only one alternator failed?
 
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Old Jun 30, 2025 | 08:29 AM
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Originally Posted by F250 Platzilla
Thanks Tsax6010. I was wondering if the percent was another feature I couldn't find. So disconnecting doesn't wipe all my personalized settings? I've never reset my "Trip 2" data because I want the fuel economy average since day 1. I would feel bad if I lost that.
I was the same way - did the same thing with my 2017 too. Then one day, I get in my 23 and all of the trip info had been reset back to zero - hours, mileage, fuel economy. Dang, I was pissed. I always reset Trip 1 but leave Trip 2 running. Not anymore, I just deselected that screen from my scrolling view and try to forget about it.
 
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Old Jun 30, 2025 | 11:12 AM
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Originally Posted by CBEllis
I was the same way - did the same thing with my 2017 too. Then one day, I get in my 23 and all of the trip info had been reset back to zero - hours, mileage, fuel economy. Dang, I was pissed. I always reset Trip 1 but leave Trip 2 running. Not anymore, I just deselected that screen from my scrolling view and try to forget about it.
Thanks! Upon reading this, I immediately ran out in the garage, and deselected Trip 2.

I did a one day, 206 mile road bike race. I spaced out at the finish line, and deleted the 11h22m data ride from my Garmin. I was REALLY pissed. I love data noodling like heart rate, elevation, average pedaling cadence... and engine hours, miles, MPG...
 
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Old Jun 30, 2025 | 12:16 PM
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I disconnected both batteries on my 2024 F350 a few days ago. Left them disconnected for 1/2 hour. When I started truck, trip 1 and trip 2 settings were just as before.
Just in case anyone is wondering.
 
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