1997 Ford F-150 XL 4.6 V8

Over the course of 2 weeks.

Battery drained and died, it was from '06 so I replaced with a new one.

Happened again re-charged battery and replaced alternator with a junk yard one and did not fix issue.

Had Carquest test, battery was fine but no output from ALT

Exchanged ALT with another junk yard one issue persist

Bought a brand new ALT Issue persist.

175 amp mega fuse is good as well as 20amp inline fuse. All grounds look good. Checked continuity on every wire from battery to ALT and show no breaks in the wires. Clean terminals and tight belt.

I am at a loss on what to do next. I have a multimeter but no voltmeter. Any relays or others fuses to check?

ANY help will be great as I need this truck for work.

THANKS TO ALL

 

I think that with the key on you should get voltage on the wire marked Batt on the back of the alternator (engine not running). An alternator needs power to make power. I believe there is an alt fuse in the cab fuse box. Check to see if you have power across it with the key on.

 

Crazy. What THE ****! All this work. Fuse #19 Airbag diagnostic moniter/Instrument Cluster in the cab had fallen out. Put it back in and alternator is charging the battery.

 

Way cool