Does anyone have a wire diagram for the alt on a 04 F250 5.4l? I replaced the passenger side exhaust manifold and now the alt is not charging. It was fine prior. I disconnected both battery cables before working on it and welding nuts on the studs. Any help would be great. Thanks .

 

Here ya go.

 

Well I have power at the B+ terminal on the back of the alt. I also have power to pin 3 in the connector when unplugged at the connector. Should there be power at one of the other pins with key on? If so where does that wire go to to trace it out?

 

of course things just keep getting better. Now the 3 pin plus will not lock in. Hope the plastic locking piece did not break. I just had to walk away and called it a day. Will try again tomorrow.

 

Can anyone tell me if there is afuse for the alt and where it may be? Also anyone know what wire should have pos + power and where it might originate from??

 

Everything in the circuit is in the diagram I posted yesterday. The charging circuit uses fuse links instead of fuses as over-current protection devices.

1. Did you fix the concern with the 3-pin plug?
2. Does the CHARGE/BATTERY light in the cluster come on when the ignition switch is turned from OFF to RUN? What does it do when the engine is started?
3. Are you able to backprobe pins 1 & 3 of that connector while it is connected and get voltage measurements with the engine running? What are the actual voltage readings fro each of those two pins, the B+ terminal and the battery positive post, all while running?