M
Mustangcwo
Guest
Today I decided to make the battery disconnect switch on my 1987 GT function properly. After reading many posts around the forums, I realized that the information is very vague and nobody explains how to isolate the alternator. Well here you go:
The stock G2 alternator wiring is as follows:
The only change to the diagram is the color of the wire and location as it hooks to the battery. The color of the wire is green (not red as shown above) and has a 14GA Fusible Link. The wire is connected to the starter solenoid and is easily removeable. Here is a pic of the wire:
Cut this wire about 2" from the fusible link and then run a wire from the battery side of your disconnect switch to the Alternator wire that was just cut.
I used a 10 gauge wire and ran it inside the car and through the firewall up to the solenoid area. Next, I crimped a fusible link between the green wire (alt out/one that was cut 2" back) to the newly run 10 gauge wire. Now, if the wire grounds inside the car, the fusible link will prevent any fires.
I fired up the car, turned off the battery isolation switch and the car shutdown immediately. :rock:
Update: I took the car out for the first test drive and the output from the alternator was not up to par. When I followed the new connection from the green wire back another 2", I found the return wire to the voltage regulator. I cut this wire about 2" back from where it joined the green wire and added a jumper wire up to the starter solenoid. Now the alternator is once again putting out full power and my cutout switch is fully functional.
The new jumper wire is only a signal wire that returns to the voltage regulator mounted to the alternator. In the diagram above, it is the yellow wire with the white stripe.
The stock G2 alternator wiring is as follows:
The only change to the diagram is the color of the wire and location as it hooks to the battery. The color of the wire is green (not red as shown above) and has a 14GA Fusible Link. The wire is connected to the starter solenoid and is easily removeable. Here is a pic of the wire:
Cut this wire about 2" from the fusible link and then run a wire from the battery side of your disconnect switch to the Alternator wire that was just cut.
I used a 10 gauge wire and ran it inside the car and through the firewall up to the solenoid area. Next, I crimped a fusible link between the green wire (alt out/one that was cut 2" back) to the newly run 10 gauge wire. Now, if the wire grounds inside the car, the fusible link will prevent any fires.
I fired up the car, turned off the battery isolation switch and the car shutdown immediately. :rock:
Update: I took the car out for the first test drive and the output from the alternator was not up to par. When I followed the new connection from the green wire back another 2", I found the return wire to the voltage regulator. I cut this wire about 2" back from where it joined the green wire and added a jumper wire up to the starter solenoid. Now the alternator is once again putting out full power and my cutout switch is fully functional.
The new jumper wire is only a signal wire that returns to the voltage regulator mounted to the alternator. In the diagram above, it is the yellow wire with the white stripe.
