I just replaced my alternator after starting to see an intermittent battery light when the engine warmed up. Replaced with a new alternator. Batterycables were cleaned prior to reconnecting everything. Engine off voltage is 12.78 and engine running is 14.54 VDC. Any ideas what to check?

 

More info - drove over to the auto parts store and had them run a test. The diode check and all the voltage outputs look good with engine running.

 

Can you post some info on your truck or complete your profile ?

 

Sure 1997 Ford F-150, 4.2L, 5 speed, ca. 130k miles. Thanks.

 

Solved. After reading every F150 battery light article I could find it seems they all end up pointing to the alternator. The new Ultima brand alternator was defective. Note this was supposed to have all factory new components. You'd think these got tested before leaving the bench.

 

Yea, ALL NEW factory components made in China or some 3rd world country you can't even pronounce the name off. That's why I don't like rebuilt alternators or starters (or most other rebuilt stuff for that matter). Only the high dollar stuff has any chance of getting parts that are reasonably equal to OEM. Tested??? I don't think you'd want to see what goes on inside a rebuild shop or see who is doing it either.

 

I HAVE THE SAME PROBLEM I GUESS i NEED TO RETURN THE ALTINATOR TO ORILEYS OR DOES THIS MEAN IT IS GOOD JUST THE LIGHT IS NOT WORKING CORRECTLY????

oops sorry for cap lock

 

I changed 2 altinators and I still dont have enough juice coming from altinator
What the heck else can it be????????????????????
Battery light still on 3 altinator installed and then tested and it is still not charging.
WHAT can it be????????

 

What do you mean Did you check the fuse for the rectifier field ?

Here is a thread on the checking of the fuse and the harness ( field ) to the alternator
https://www.f150online.com/forums/el...nator-why.html