I have a 1966 Mustang with a 289 2bl carb and auto transmission. Everything was working fine untill the other night. My son was driving and he had the wipers, radio and the defroster on. As soon as he turned on the head lights the car went dead. No power to the inside of the car at all. The battery is good and I have power to the starter solenoid and the voltage regulator. No power to the fuse box and all the fuses are good. Any ideals ?
Thanks, Randy
Did you check the connection between the regulator and fuse box? I had an issue with my 66 where one of the connectors overheated mealting the jacket around the wire and causing it to short out. After hours of searching I finaly found that the the connectors in my high/low beam switch had mealted and were grounding out. It is possible that maybe an old section of wire overheated somewhere between the fusebox and voltage regulator and is now grounding out. I have noticed that with the original wireing it tends to build up a lot of resistance over the years which is especially bad at the connection points. I even had the main connection in to the fuse box start to over heat and melt part of the box on another old mustang I had. With all of your excessories turned on I would be suprised if that were the case.
I hope that can be of some help.
-DCH
Trace by sight and color from the starter relay to the fuse box.
Probably a blown fuse-link... this is a selected resistance wire in the leads.. or a connector crimp that has oxidized slowly and finally given up... should show some signs of overheat as DCHUNT says.
If a fuse-link... there will be a 'factory-splice' to the standard wire... fuselinks are more flexible is one way to tell them. If it is that... replace with at least a 30 amp fuse link
on the front side of the starter solenoid ( side closest to the battery) should be a ring terminal with a black wire that has a yellow tracer on it. This wire goes through the main harness. I believe on the 66 model it is one of the two odd wires in the connector (i.e 2 are female the other six are male and vice versa for the under dash plug) this wire should junction right before the fuse box a from the split a yellow wire to the ignition switch, a black wire with orange trace to the headlight switch, and the original black with yellow goes to the fuse box. I believe that you will find that the
64-66 mustangs do not have a headlight fuse as they are internally protected. so if you have no power anywhere. I would check the black wire with yellow tracer using a piercing probe, to find the break/shorthope this helps
walt
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