1994 Ford Ranger Repair Question
My alternator quit charging and I have tried 4 other alternators and none have worked, all 4 came from junkyards.
Here's a diagram of your charging circuit
Imma CJ Jeep kinda guy--I can maybe help you with the diagram--I know little about your rig
here ya go.
I have the 2nd diagram and have been working off of it, the battery light comes on so I have 12v thru that wire (LG/R), I also have 12v at the (Y/W) wire and 0v on the (W/BK) with key on engine off.....I have only seen 1 fusible link by the solenoid and it checks out good with 12v at the back of the alternator. Fuses all check out good but no charge when running.
i always take the alternator to the auto store for testing when i get them from bone yard. that way i know any problems originate with vehicle.
I made the alternator work by running 12v to the G/R & Y/W wires so I know the alternator is good, took the 12v off the Y/W wire and get no charge so I ran 12v from battery to Y/W wire only (OE wiring on G/R) and get charge but the battery light stays on in the truck, getting about 14.6v to the battery now. Battery charger is on now charging it because it was down under 12v. Thru the OE wiring when running I had 1.9v on Y/W wire and 6v on G/R wire, tried different fuses in power box under hood( 40a & 15A) with no changes. Something is still wrong but at least I know the alternator is good.
CHECK YOUR FUSES!---YOUR OWNERS MANUAL MAY SHOW YOU LOCATIONS THAT YOU KNEW NOTHING ABOUT!
REMOVE AND REPLACE "SUSPECT" FUSES SEVERAL TIMES--THIS MAY SCRAPE OFF CORROSION AND GIVE THEM BETTER CONTACT!
Are the wires to your solenoid hooked up correctly?
Try the stuff below (actions),
IN MOST CASES THIS IS THE PROBLEM!
PEOPLE GET LAZY!----THEY DO NOT ACTUALLY DO THIS STUFF
IT BITES 'EM IN THE BUTT...THEY COULDA BEEN RIDING LONG AGO!
TAKE STUFF LOOSECLEAN"SCOOCH" THE CONNECTORS AROUND----TIGHTEN THE NUTS OR BOLTS WELL!!!! DO NOT JUST PASS OFF ANY BIG CABLE CONNECTION AS, "IT LOOKS GOOD".
DIELECTRIC GREASE IS YOUR FRIEND!!!, APPLY TO CONNECTIONS--FUSES--RELAYS ETC.
KEEP US POSTED
Fuses are all good, tried other fuses from my wife's car. Solenoid wires have not been touched in years, everything else works properly other than the charge circuit, I will try unhooking the solenoid and cleaning the terminal to see if that makes any difference but it shouldn't, the Y/W wire comes from the power box under the hood not straight from the solenoid. The things that I wonder about is if there is another fusible link somewhere that I have not found, and why does the voltage on the Y/W wire drop from 12v down to about 1.9v after starting the motor? I have a Chilton manual and have the wiring diagram for a 94 ranger and it shows the Y/W wire being straight thru from the 15a fuse to the alternator. I went and bought wire and connectors today so I can replace the wire tomorrow and see if that makes any difference.
OK THE PIC I POSTED EARLIER WAS NOT THE ONE I MEANT TO
I WENT BACK INTO MITCHEL I, THIS IS THE ONE I MEANT TO POST
I REALLY HOPE WHEN YOU CLEAN THE SOLENOID CONNECTIONS, ALL WILL BE GOOD....ANY OTHER CONNECTIONS THAT ARE THERE (SNAP TOGETHER SMALLER WIRES, IN THE SYSTEM) MIGHT PULL THEM APART A FEW TIMES, DO THE DIELECTRIC GREASE THING TO THEM ALSO.
HERE'S THE RIGHT PIC
KEEP US POSTED
yah, that 1 only shows 1 fuselink. which is what he has.
HOW ARE YOU DETERMINING YOUR VOLTAGE
GAUGE IN TRUCK---OR A PORTABLE VOLTMETER?
JUST FOR MAKING SURE YOU DO NOT KNOW ANOTHER FELLER WITH A POST HERE, THE TRUCK MUST BE RUNNING IN ORDER TO CHARGE THE BATTERY!
IF YOU HAD ONE OF THESE, YOU'D BE RIDIN' RIGHT NOW....LOL!