F150 alternator upgrade

[Jtrussell1890]

'07 F150 King Ranch Supercrew 4x4

So recently I upgraded the factory 110a alternator to the 130a. The new alt has an external regulator with additional wires than the factory set up (D style plug with 4th wire on a single pin as well as the main battery cable on the separate post vs the factory 3 wire oval plug and the main battery cable on the post).

My current issue is that, while I am seeing 13.9 to 14.5 volts at the battery and all of my accessories are working as intended, my battery light on the cluster stays on and the message center says "Check Charging system" every 5 minutes or so.

Any ideas?

 

[franklin2]

Most likely you are messing with one of those advanced charging systems. Like everything else, the OEM's have gone a little crazy looking for fuel mileage. They have the charging system tied into the computer system. It monitors what is going on and if it senses the chance, it will turn the alternator down to a lower output to save fuel, but still be enough to keep things going.

More complication, more things to break. See if your original system was tied into the computer.

 

[Jtrussell1890]

I'm thinking it is because I do know that one of the wires in the original harness is what decided the "load" needed from the charging system. This where I'm running into my issue. I know people upgrade these systems quite often for other things like stereo upgrades, extra lighting and other electrical accessories. I just am not aware of what I missed or how to correct my own issue. My goal is to eventually add an amplifier and small subwoofer as well as a small amp for the other speakers to get a better quality sound and to add some accessory lighting in to the bed for some cargo lighting.

 

[lil_Blue_Ford]

My 95 F-150 threw a battery light when I replaced the heavy wire from the output stud on the alternator to the battery with a piece of 4-gauge welding cable. I reconnected the stock wire on top of the welding cable and the light went out. Even back then it must have somehow monitored the stock wire. Still don’t understand how though

 

[Jtrussell1890]

So, been doing a little research on this lazy Sunday. On the original wiring, there are 3 wires in the plug. Battery signal, Generator Monitor, Generator Communication. The Gen Com line sends info from the PCM to the regulator, the Gen Mon line sends info from the regulator to the PCM and the Battery signal line detects battery voltage from the battery and is connected to a fusible link and then the battery.

The original system is using an internal regulator style of alternator and as far as I can tell, there isn't an internally regulated alternator that is more than the stock amperage (110amp). The current alternator I have installed is an externally regulated 130amp Motocraft that I think also fits and F250. Maybe I need to look into the super duty charging system and see if there's a cross over I can manipulate to work in my favor.