Uh, no.
'Under your theory, the voltage regulator would be able to "adjust" if voltage at the sense wire was at 12-14 volts.'
Not at all if the regulator is defective, I've seen so many variations away from that it's silly to even say it.
And 120 amps will be quite a bit higher than 14 volts too, need to get your meter checked there. Volts ALWAYS increase with amps. The alt should make around 75-100 volts with no load or regulation on it.
'The maximum amp charge to the battery should be no more than 4.5 amps at any time.'
ABSOLUTELY incorrect, I have seen countless systems go up to 20 amp or more right after a start and that was on 40 amp systems way back in the '70s, the modern fast charge alts can go much higher than that but they then choke back down quick (they BETTER) or then things begin to burn up. You don't burn up a battery at 10 amps, they commonly put out up to 250 at starting and up to however length of time somebody is dumb enough to crank the cars for. With complete system draw and all things working the battery can easily put out 10 amps at all times now and meaning that much must be going back in just to stay even, never mind any overhead. A rear glass defroster alone can pull up to 5 amp.
Take a 6G PCM controlled alt, it will easily charge 10 amp at idle and WAAAY higher than that if demand is put on it and why so many of them go bad, even brand new ones when dopey people insist on using the new alt to recharge the dead battery run down by the dead alt before. I voided so many warranties over that I cannot count when I was in parts, every piece of alternator literature on the planet now says to NEVER do that, the battery will not harm at all from it but the alt will burn out the regulator in minutes doing it. By Ford themselves it takes 8 HOURS to fully charge a dead otherwise good battery all the way back up with an alt and in the service manuals as NEVER DO IT. The alts are delicate enough even that a battery not bad but getting close commonly shells the alts out now, they again overheat at the reg long before the battery overheats and while trying to fill up a battery that never fills due to being old. On the Focus websites I have corrected hundreds of people that shelled out alt after alt and battery finally changed and the problem is gone, but only after you tell them. And that is on batteries that WILL pass a loadtest but on the low end of the spec.
Not saying the cluster was not the issue there, just that the 3G alt used there had no PCM control on it. I need no overall understanding of the complete system to pick up on that cluster alt light schematic and working method, I have seen it hundreds of times and up to 40 years ago.
'Under your theory, the voltage regulator would be able to "adjust" if voltage at the sense wire was at 12-14 volts.'
Not at all if the regulator is defective, I've seen so many variations away from that it's silly to even say it.
And 120 amps will be quite a bit higher than 14 volts too, need to get your meter checked there. Volts ALWAYS increase with amps. The alt should make around 75-100 volts with no load or regulation on it.
'The maximum amp charge to the battery should be no more than 4.5 amps at any time.'
ABSOLUTELY incorrect, I have seen countless systems go up to 20 amp or more right after a start and that was on 40 amp systems way back in the '70s, the modern fast charge alts can go much higher than that but they then choke back down quick (they BETTER) or then things begin to burn up. You don't burn up a battery at 10 amps, they commonly put out up to 250 at starting and up to however length of time somebody is dumb enough to crank the cars for. With complete system draw and all things working the battery can easily put out 10 amps at all times now and meaning that much must be going back in just to stay even, never mind any overhead. A rear glass defroster alone can pull up to 5 amp.
Take a 6G PCM controlled alt, it will easily charge 10 amp at idle and WAAAY higher than that if demand is put on it and why so many of them go bad, even brand new ones when dopey people insist on using the new alt to recharge the dead battery run down by the dead alt before. I voided so many warranties over that I cannot count when I was in parts, every piece of alternator literature on the planet now says to NEVER do that, the battery will not harm at all from it but the alt will burn out the regulator in minutes doing it. By Ford themselves it takes 8 HOURS to fully charge a dead otherwise good battery all the way back up with an alt and in the service manuals as NEVER DO IT. The alts are delicate enough even that a battery not bad but getting close commonly shells the alts out now, they again overheat at the reg long before the battery overheats and while trying to fill up a battery that never fills due to being old. On the Focus websites I have corrected hundreds of people that shelled out alt after alt and battery finally changed and the problem is gone, but only after you tell them. And that is on batteries that WILL pass a loadtest but on the low end of the spec.
Not saying the cluster was not the issue there, just that the 3G alt used there had no PCM control on it. I need no overall understanding of the complete system to pick up on that cluster alt light schematic and working method, I have seen it hundreds of times and up to 40 years ago.