Charging problem

[Dirt Rider]

I have a new re-manufactured alternator that has tested out good, it's working when I hit juice to the field wire, but it's still not charging my battery. I've run through all the tests and everything checks out okay, but I can't get the battery to charge. It's a good battery, so that's not it. Very frustrated. I've tried everything. Any ideas?
It's a 2000 Ranger, two-wheel drive, 4 cylinder

 

[Johnharrison531@yahoo.com]

Answer to charging problem

With all those parts replaced and good working order now you have to check for open circuits your engine compartment fuse box check your diodes and what they call a alternator field fuse if it is blown the alternator will not charge because the charging circuit is open hope this helps you out!!!!

 

[Johnharrison531@yahoo.com]

Check your diodes and in engine compartment fuse panel look in your owners manual for a alternator field fuse if its blown the charging circuit is open and alternator cannot charge hope this helps had same problem on a f150

 

[ab_slack]

My question is how do you know the alternator is not charging the battery? This is more a sanity check question.


You said " it's working when I hit juice to the field wire" which suggests you know more than most about how the alternator works and thus probably know what you are talking about.

So I am guessing when you measure the battery voltage with the truck running you see some low voltage as if it was off and when you put some power on the field wire the battery voltage climbs to the normal float about 14V.

In that case, it seems pretty simple the problem, the power to the field wire isn't there in which what has already been suggested would be where to look.

 

[RonD]

Check the voltage at the B+(larger wire) on the alternator, engine off, if it is 12volts then connection to battery is good.

One of the smaller wires on the alternator is green, that's the wire that turns the alternator ON, with key on, engine off(KOEO) that wire should have 12volts.
That 12volts comes from the ignition switch, via a 7.5amp fuse in the inside fuse box.
the fuse number in the panel changes from year to year, but check all the 7.5 amp fuses.