Mechanics

WHAT NEXT WITH CHARGING SYSTEM??

1994 Ford Ranger • 147,000 miles

Still having the same problem with alternator not charging battery. Unplugged the instrument panel, thinking it was faulty because gauges are not working. Pulled one fuse at a time while using multimeter to check for short. I'm not getting any return charge voltage back to battery. Alternator has now been checked twice and tests good. Battery is new. I've traced wire that I was told by a ford tech that is the return feed from the alternator to the battery. Odd thing. It reads the same voltage as my battery, not the 13.2 to 13.8 that it should. I am running on the battery which isn't going to last much longer. Please help!
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Kent46725
May 9, 2012.



Test the voltage at the main terminal of the alternator with the key OFF? What is the voltage?

Wrenchtech
May 9, 2012.
Starting voltage was 12.4, after driving it for 2 days it has dropped to 11. I am getting the same voltage at the alternator main as I get at the battery.

Tiny
Kent46725
May 9, 2012.
That's not what I asked to to test.

Wrenchtech
May 9, 2012.
Close to 12v like I already said. With key off.

Tiny
Kent46725
May 9, 2012.
Was this tested with the key OFF?

Wrenchtech
May 9, 2012.
Yes, key off.

Tiny
Kent46725
May 9, 2012.
Test for power on the yellow/white wire all the time and the lt green/red when the key is on.

Wrenchtech
May 9, 2012.
Ok I am at work, so will do afterwards. I think I had checked voltage on the y/w wire and have voltage there. But don't recall getting any at that point, but will test again and let you know. Thank you for responding so quickly.

Tiny
Kent46725
May 9, 2012.
Ok, pwr at y/ w constant. No power at g/ r wire when on. Next?

Tiny
Kent46725
May 9, 2012.
OK, that wire runs from the ignition switch (gray/yellow) through the fuse panel and then to the charge light (gray/yellow) and from there to the alternator (lt green/red) and the circuit is broken somewhere. You are going to have to locate that wire and determine where it's losing it's power. I would be very suspicous of the fuse panel although it's just a splice. It doesn't pass through a fuse.

Wrenchtech
May 9, 2012.
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