Ford Powerstroke Diesel Forum banner

2000 7.3 new alt. new batt wont charge

2K views 3 replies 3 participants last post by  symbols 
#1 ·
Hi all. I have been messing with this for a couple of days now and am getting frustrated. I have a 2000 7.3 and while plowing snow, my batt light came on. I hooked up dvom and only had 11.8v running. Bought a brand new CARQUEST alt. not reman, brand new. put it on truck, charged batts fired it up, only 12.3v. checked the fuses, all good. Checked voltage at orange and green wires at alt, key on engine off they show 12.3v batt voltage. start vehicle and orange wire and green wire both show 13.6v, but the power from alt to batt is only 12.3v. this told me alt was no good. took it back to store they tested it good, but gave me a new one anyway. I put it on the truck and same prob. Is there something else that i am overlooking? has anyone else had this same prob? please help. thanks
 
#2 ·
If you have 13.6v at the alternator and only 12.3v at the batt. there is something you missed in the wiring. Trace the charging wire from the alt. to the batt. If this happened while plowing, you most likely blew a fuse. I don't have a wiring diagram in front of me or I would point out most likely places to look.
 
#3 ·
:-{

The only wires that have 13.6v is the small wires coming out of the plug on the alt. the charge wire is only reading 12.3v batt voltage and i tested that directly at the rear of alternater on the stud. now get this, this morning went and fired the truck up and only 12.01v at batts and charge wire on alt. small wires on alt had 13.66v. drove it to work about 15mins. tested it there and both batts and charge wire read 14.1v while running. went to go to lunch fired it up only 12.8v at batts and charge wire idling. I dont know what is going on with this truck. it's like it charges when it wants to.
bang2: :icon_ford:
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top