Hey guys, recently purchased a 93 ranger. And I drove it home, let it idle amd it slowly died on me. Tried to turn it back on and got a VERY loud and fast clicking. Like a when you have a dead battery. So I charged it and also thought well... The alternator could be bad as well because it was running then died. So o replaces the alternator and now the power wire from alt to battery is sparking like crazy and caught on fire. Can't connect it to the post or it will just keep sparking. And now truck wont start. I get check engine, battery, and abs light when I put key in ignition. When try to crank it absolutely nothing.

Anything helps at this point.
thanks.

 

Well come to the forum

Alternator wiring is very simple

On the back of the alternator is a stud with a nut, thats the "B+" terminal.
B+ connects to Battery positive with a MAXI Fuse or a Fusible Link.
Google: Ford fusible link
if you are not sure what that is, just a short wire, but a special wire

The alternator also has a 3-wire connector, with Yellow, Green and White wires
Yellow wire is similar to B+ wire, just smaller, it is also connected to Battery positive and will have a fuse in engine fuse box(15 amp) look for Alt Fuse

Green wire is connected to the Battery Light in the dash, this is also the ON/OFF switch for the alternator

White wire is just a jumper from internal Voltage Regulator to Rotor.

Alternator B+ terminal is not connected to a Ground internally, so if you connect it's wire to Battery Positive and get a spark then either the B+ wire is shorted or alternator is, internally, so bad alternator.
Unwrap and expose all of the B+ wire, fusible link may have melted and is shorting out.

remove 3 wire connector
Test for voltage at yellow wire, should be the same as battery voltage
Test Green wire voltage, key off, should be no voltage
Turn key on, you should now see battery voltage on Green wire


1993 should still use Starter Relay(solenoid) mounted on the inner fender
One of the large posts will have many wires, the other large post only 1, to starter motor

Remove all the wires on the "many wire" post, this post is the "Power Distribution" for the whole truck, all power from battery or alternator flows thru this one connection
Make sure all ends are clean, no corrosion.
Put Battery positive cable on it first, the B+ wire from alternator, there should be no spark, unless there is a short
Put all wires back on, tighten nut

 

Awesome thanks for the fast reply. Ill give this a shot. And that short shouldnt have any effect like, burning the whole wiring harness.

 

All wires to positive battery terminal should have a fuse or fusible link.
BUT........truck is 24 years old and is probably not a 1 owner vehicle, so...........

Any previous owner could have added unfused wires, which can short and melt, taking/melting other Factory wires with it

And I have seen more than a few Fusible Links cut out and/or bypassed

And most people have seen a penny or a nickle used as a fuse, lol
Or how about a .22 cartridge............."hey it fits"

 

Okay. Thanks again!

 

Hey so I bought a alternator and put it in. When I went to put the negative side back on the battery it just obliterated the wire again... So thinking I have a short. But where? It didn't do this until I changed the alt. But I only messed with those 3 wires nothing else.

 

You will need to unwrap the wire harness and expose ALL the alternator wires from alternator to Starter Relay and engine fuse box, there is a short to another wire in there

You assume the reason the truck die and wouldn't restart is because of the alternator or its wiring.
But there could have been another reason, so ONLY messing with the 3 alternator wires might be the problem.........could be another wiring issue you haven't found

 

Quick question. If my alternator is bad could that cause it to burn that b+ wire?

 

Yes, you can test that with an OHM meter
Select 200 ohms on meter, if it has that selection
Touch probes together to test, should see 0 ohms
Touch 1 probe to B+ terminal and the other to Alternators case, should read N/C(no connection), no change, or very high OHMS, if 0 ohms then there is an internal short