I'm currently running into trouble connecting the inductive loop ammeter that resides in the Mustang's gauge cluster. We already put the black wire (the one with the yellow stripe on it) through the hole but can't find any information on how to proceed from here :(

Anyone had the same issues and knows how to connect it?


Here is a picture from Mustang Monthly. The description in the article that is from says:

In '65, Mustangs had an induction-style ammeter with no connections, only an induction loop (also called a magnetic loop) on the back of the ammeter that picks up current flow (magnetic field) through the main power lead.

That all sounds fine and dandy unless you don't know how that black/yellow wire is supposed to be connected. This post hints at it. More info.

I don't know what state your cluster wiring harness is in, hope this gets you going.


In '65, only Mustang GT's and Mustangs equipped with the Deluxe(a/k/a Pony) Interior had an actual ammeter, as opposed to an idiot light. This was an induction-loop ammeter, not the shunt-type ammeter that was used in '66 models and beyond.

The hookup is as follows... A BLACK/YELLOW wire runs from the Alternator, through a 3-wire pigtail, under the radiator bracket, along the driver-side fender apron, and ends at a Main Disconnect Harness on the firewall near the master brake cylinder. That BLACK/YELLOW wire then emerges on the inside behind the instrument panel and passes through the loop on the back side of the ammeter gauge. After passing through that loop, the BLACK/YELLOW wire plugs into (via a bullet connector) a heavy-gauge BLACK wire. That BLACK wire then continues through the firewall (through its own rubber grommet), runs along the firewall toward the passenger-side fender, and ultimately attaches to the BATTERY side of the solenoid/starter relay.

And just as an additional FYI, if that circuit loses continuity at any point, the car won't start.

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