Dual alternator install: now code p1106.

[410sn95]

I did do a search but came up with threads that were somewhat vague as to what needs to be done.

The truck: Early 99 7.3 4x4 single alt. truck.

I installed the second lower alternator using all FORD parts. This includes harness, alternator, Bracket, etc. The install went very easy. I plugged in to the factory plug on the truck for the 2nd alternator, which is behind the passenger side battery (Which did have a dummy plug as a place holder) and the power wire went to the power lug on the inside fender.

I am getting a p1106 code now (lower alt. control fault). Anybody know if you do INDEED have to get a reflash from Ford? I know the 2nd alt. is doing something as my idle voltage jumped from 13.5 at idle to 14.08. It's rock steady at any engine speed. Anybody done this swap? Any help would be appreciated.

[The Hosser]

the cpu was set up for single alternator and now is reading that it has a 2nd. it was programmed for only one. it will have to be reprogrammed to see that it has a second alternator. otherwise you will just continue to see the same code. has to be reflashed but i do not think that ford will have to do it. you might have some luck with an aftermarket programmer.

[jesilvas]

Would it hurt anything to keep running it w/out reflashing it?