[ajzride]

I'm a bit stumped, and I'm hoping you guys can help me out. I've got a key-off battery drain that I can't track down.

First off, here is the wiring diagram that I am trying to use as a guideline:



And this is how I am currently wired up (don't laugh at my mspaint skillz):



The little boxes with the x in them, are some sort of plastic piece in the factory harness, that I don't know what goes on inside of them. I'm assuming that they just help turn wires in the right direction, but I can't be positive.

Everything from the connector on the alternator pig tail (3) back is wrapped in the factory tape, and I don't see any damage to it anywhere.

As things are wired up now, i have a 2.6 mA drain. If I disconnect the Alternator pig tail, the drain goes to 0. Moving back, if I disconnect the regulator, the drain goes to 0. If I unbolt the alternator and hold in my hand away from the firewall, the drain goes from 2.6 to 1.8 mA. Moving even further back, if I unplug the main disconnect, the drain remains 2.6 mA.

This seems to indicate to me that the drain is in the engine compartment, and not related to anything beyond the regulator.

If I disconnect wire 1 (a single yellow/black wire) The drain goes to 0. If I disconnect wires 2 ( a single yellow wire and a single black wire fed into a common eyelet) the drain goes to 0. However, if I disconnect wire 1, the battery does not charge. If I disconnect wires 2, I get no power to the ignition switch, so no power to the distributor or solenoid.

I can't see any damaged wires under the hood, and everything appears to be connected properly. The regulator is brand new, but is it possible that it is the culprit?

I'm open to any suggestions, I'm pretty handy with a multi-meter, and I'm pretty sure I can follow any directions you guys throw my direction.

Thanks in advance for all of the help.

[MustangOne]

Unplug the voltage regulator see if it goes away. if it does replace.

If not unplug the headlight side wiring see if goes away.

If it does its inside.

[ajzride]

It definitely goes away when you unplug the regulator. I'll swap it this weekend and see if that fixes it. Headlights are not installed, so I can't unplug them.

Thanks MustangOne.

[MustangOne]

Unplug the voltage regulator see if it goes away. If it does replace it.

Then it is fix go not farther.

When I said, If not unplug the headlight side wiring see if goes away.

I meant where it is plugged into the under dash wiring. Not the headlight bulbs.

Just to clear it up for anyone else who may read this.

[ajzride]

Okay, I see. I don't think that will help though, as unplugging the main disconnect beside the brake master cylinder does not make it go away.

Thanks

[MustangOne]

If Step 1 fix the problem, Step 2 is pointless.

[ajzride]

Swapped the regulator today, no change in status.

Also, a correction, I do not have a 3.6mA drain, I have a 3.6A drain, much much bigger, and a much larger problem.

When swapping the regulator did not fix the problem, i started pulling wires one by one to see what would make the problem go away. I arrived at the "Field" wire on the alternator (the white wire). Pulling the field wire solved my problem. Well, it stopped the drain, but it also prevented me from charging. I carried the alternator back up to Advance and swapped it out, but that still did not solve my problem.

At this point, I started doing continuity checks to find out where the factory wires that were all wrapped up and ran behind the frames were actually connected to. What I found was that the large Black and Yellow wire (wire 1) went into the harness connector (3) but on the other side, it went into a black/white (inside wrapped wires) which was destined for the Regulator's Stator connection. According to the alternator diagram that came with my alternator, the stator terminal (at about 11 o'clock if you are looking at the back of the alternator) should remain unconnected. But regardless, I don't think that 14V coming off of the BAT connection (about 2 o'clock) on the alternator should be going to stator tab on the regulator.

The car had no motor when I got it, and it also did not have the alternator wiring harness. I ordered this one:

Mustangs Unlimited - The Premier Source for Mustang, Shelby and Cougar Parts and Accessories

But since my car was originally an I6 with no gauges, I'm wondering if that caused the problem with the Alternator BAT wire going into the Regulator Stator plug.

I disconnected this wire, but I have not solved my problem.

The only idea I have at this point is that perhaps having the wiring harness wrong, I have been zapping a diode in my alternator, and now that I have the 12V disconnected from the regulator stator port, I need to put in one more new alternator, and hopefully not blow it.

Any other ideas guys?

Thanks

[MustangOne]

Did your car have the 5 gauges? That is what you bought. or the 3 gauge set up?

3 gauge set up.



1965 5 gauge set up.




If it was the 3 gauge setup you have the wrong alt wiring.

[ajzride]

It currently has the 3 gauge setup, but I've bought a 5 gauge to install soon.

[MustangOne]

Did you buy a 3 or 5 alt wiring?

If you bought a 5 you will need all of the wiring not just the alt feed. They wired differently.

You can add a 5 gauge set to a 3 gauge wiring with little effort. But you can not mix and match the wiring parts.

[ajzride]

Well darn. Is my best bet to order the 3 gauge harness, and then run new wires for the extra gauges?

Thanks MustangOne

[MustangOne]

yes, and the wire is already there for the extra oil gauge.

You just have to add a extention and gauge oil sender.

Good Luck, Let me know when you switch it over and I will give you more info.

[ajzride]

Bought one of these, since my car was an original 6cyl with warning lights. I'll let y'all know if I have any more problems.

https://www.mustangsunlimited.com/it...asp?T1=AH11+01

Thanks

[MustangOne]

Good Luck.

[ajzride]

Installed the proper wiring harness this weekend. Ohmed everything out, and the wires go to the right place now. However, the drain remains. I think I have narrowed it down to the alternator, which supports my theory that having the wrong harness in place blew a diode. I will swap the Alternator when I get a chance, and hopefully I won't blow it down that I have the correct harness.