Switched 12v wire?

[Alex L.]

Can someone help me out and tell me what wires in my 57 500 are switched 12v? i am going to be upgrading from a 1g to a 3g alternator on the 351 windsor and i need a switched 12v to hook into, i will also be putting in a new stereo and i will need it for the remote wires. Any help is appreciated.

[Ford Blue blood]

If I remember correctly (manual is in the shop) the center post is the ACC position.  This is hot when the switch is in run and ACC.

[shopratwoody]

I can't remember for sure either. When the ign sw is dropped down
below the dash double check with tester.
Ron

[Alex L.]

I've done some hunting. Apparently the (+) positive wire on the ignition coil can be used to trigger the alternator. Who knew?

[canadian_ranchero]

check for a resister on the coil wire,you will not get 12 volts on the wire if it does

[shopratwoody]

I don't like the idea of using coil wire IMO. Just seems Micky

[Alex L.]

I don't like the idea of using coil wire IMO. Just seems Micky

You do have a point there, it is pretty lazy compared to just crunching the wiring diagram and finding a wire that will work.

[shopratwoody]

I wired mine a few yrs ago, isn't just the start wire on the sw?

[cool57]

One side of the headlight switch is always hot.

[shopratwoody]

On my car when I raced it the guy that wired it put a sw to turn
the alt on or off. If I left it on when the car was off the btry went dead.

[iamflashman]

Just use the ACC on the ignition switch.  It is the perfect wire for a stereo since you want your stereo to work in both ON and ACC position.

If you drop the ingnition switch down, you will see the posts are labelled.  Just use a crimpon eye connector on the ACC terminal and you have a switch 12V.

To make adding accessories easier, I actually install a fuse block at the top of the kick panel area that has a bank for IGN and a bank for ACC fuses.  Then, when you add a new accessory, just pop in a fuse and run a wire.

You can get inexpensive fuse blocks at Autozone or really nice ones from Painless wiring.

Good luck!

[Alex L.]

I finally got around to popping the ignition out and will be putting in a fuse block so i can have multiple switched 12v circuits.

Can anyone confirm that the center terminal is in fact the ACC terminal?

[Ford Blue blood]

Alex forgot all about this thread.  The center terminal is hot from the battery.  You have three other terminals that come off the side of the switch.  One is the start to the starter, one is hot in run and the third is hot in run and acc.  The start wire isred/blue band, the run wire is red/green, the acc wire/s blue/green and the 12V hot is yellow.  Small gauge blue/green is found on both the run and acc, run to power temp and fuel, acc to power the idiot lights.  Hope this helps you out.

[Alex L.]

ok, i should be able to figure it out.

Thank you muchly

[Alex L.]

Man, I'm a dummy. Once i cleaned the dust off of the ignition cylinder the terminals were marked.