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Charging ?'s help!!

  • Thread starter Thread starter former honda
  • Start date Start date Mar 3, 2004
F

former honda

New Member
Mar 3, 2004
2
0
0
Mar 3, 2004
#1
  • Mar 3, 2004
  • #1
First off I'd like to say high as i'm a new mustang owner as of today. Being that I sold my honda to get my mustang i'm still getting used to this thing called torque. Anyway i'm having a problem with the charging system. I've searched but still haven't found what i'm looking for. Background info:

-New alternator thats already been checked (internal VR)
-87 coupe former 4cyl car
-Car was sitting for a month and when I went to test it the owner charged the battery and installed the battery leads backwards resulting in the smoking of the starter solenoid and a fusible link to the ignition. (Has been repaired)

My problem is my alternator is not putting out anything. I'm getting 12.5v with the car off and 11.9 or so with the car running and the indicator kight in the dash is on. I've checked the wires too and from the alternator and they all have continuity. My problem with using a wiring diagram is that I don't know if there is any difference between a 4 cyl alternaor harness and a 8cyl alt. harness.

All together there are 6 wires at the alternator. 3 in each plug. Both thick black wires have ~12v with the car running while the creamy white wire that runs to the other alternator plug only has .1v. It seems that it's a signal wire possibly from the voltage regulator to the other harness. Is that the case and if so is that too low of an output???
The other harness has a yellow wire (also with 12v running) a green wire with 5v and the same creamy white wire that jumps from the other alternator harness.

The negative battery terminal was extremely corroded and was replaced. The 2 thick black wires from the alternator harness splice into 1 six inches from the alternator plug and are also very corroded. Is that a factory splice or was it rigged that way?? I plan on replacing the two black wireswith a completely new wire tomorrow from the alternator to the solenoid.

Any ideas on whats going on? The wiring other than the corroded thick wires from the alternator seem fine and have continuity which would make me think its the alternator but it checked out fine. Help

-Cliffs notes: New mustang owner. Car won't charge. Alternator checked, wiring seems good other than one corroded power wire.

Sorry for the long first question. Also is there some sort of factory service manual as opposed to the haynes or chiltons manual?? Thanks in advance
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Mar 3, 2004
#2
  • Mar 3, 2004
  • #2
I'd run it by AutoZone or Sears and let them load test the alternator and the battery - after that backwards hookup, all sorts of stuff can be fubar. The alternator ought to put out between 14.0-14.4V when the engine is running. However, a bad battery can impact that. You say the alternator's been checked - implying it's ok; but then you say it's not putting out anything. So I'm confused -- if you haven't had both alt. and battery load tested, I wouldn't try anything else till I did that. After you're certain you've got a serviceable battery and alternator then you can start checking out other things that might have been fried in the unfortunate incident. Welcome to the world of torque, and heaven help you for buying a car from an owner that didn't know how to hook up the battery properly. Good luck with it.
 
F

former honda

New Member
Mar 3, 2004
2
0
0
Mar 4, 2004
#3
  • Mar 4, 2004
  • #3
Thanks for replying. The alternator was tested and is putting out the amount of amps it's supposed to and mid 14's in voltage which would be great only if it did it on my car.

The battery is new and after charging it I used a load tester at the vw shop I work at and it's fine too. I'm hoping the corroded wire is the culprit. I'll find out tomorrow.

Oh also luckily the guy who installed the battery leads backwards was the father of the owner. His son got stationed in Germany and his dad sold the car for him. Thanks for your help. Take it easy
 
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