Ford Powerstroke Diesel Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
Ok I have a 2000 7.3 f350 and I have a new alt, batteries. And I am getting 0 volts off the alternator.I took the alt back and had it tested again and Napa's tester says its good, The wires on the 3 pin connector both have voltage when running and only the orange one has power when it off. Any ideas I have tried everything I could find online to no avail. Thanks. Scott
 

·
Premium Member
Joined
·
8,475 Posts
Remember, the Alternators output is controlled by the PCM so that, when the GlowPlugs are ON, it doesn't "overtax" it. That means, you actually won't see any output from the Alt at first...

If you're waiting long enough to test and are sure the Alt, itself, is good. And sure it's not about a connection anywhere, maybe the PCM isn't "turning it on"?
 

·
Registered
Joined
·
3 Posts
Discussion Starter #3
Ok after doing more reading and testing on the truck I have found that the alternator is not exciting I ran a jumper wire from the switched side of the starter solenoid and bingo it starts charging but when I did that it made the starter continue to spin, any ideas were the problem is I really don't want to have jumper wires running around on this thing?
 

·
Registered
Joined
·
3 Posts
Discussion Starter #4
Just did more testing, the green wire that does the exciting is working properly the orange wire is hot and it charges when you are cranking the starter, but as soon as the truck is running it drops to 0 volts at the back of the alternator. Also the battery light Is working. I tried unhooking the battaries thinking maybe it's a PCM problem but no change. I really need this truck up and running so any ideas would be greatly appreciated.
 

·
Registered
Joined
·
2,200 Posts
No help, but here's a bump for ya in case someone else has a bright idea. :)
 

·
Registered
Joined
·
16 Posts
AKscott.....did you ever get this problem figured out?? I'm having the same issue.
I get power reading at the control and switched wire with the key on, but not enough to light a test light. The multimeter reads voltage but when I try the test light it drops to 0.
 
1 - 6 of 6 Posts
Top