Gauges and electrical gremlins

[stackattack]

I was trying to help a buddy out today with his car. He has gauges that will peg (jump to full) whenever you turn the ignition on. After digging around the dash and finding all kinds of historical $%^kery we still have a few issues. Two gauges still "peg out" when powered. But, this thing has really got my head scratching. After looking around and tracing lines, etc we found this on the firewall pass side of the car. It has positive feed coming from battery and a bunch of other powered things on the far right terminal. We are tracing whats on the 2 terminal (left right as you face it) but there's another large feed wire on the first post that appears to go down to starter.

That said, powered on or not I can only get reads on the 4th post (the one with all kinds of leads attached). It is constant power. The other 3 don't seem to do anything...

Can anyone tell me what the heck this thing is???

 

[stackattack]

Never mind. Its a mess but its the solenoid. No ground on post 3 though

 

[67Dart273]

BE CAREFUL!!! There are many ways that solenoids can be wired/ manufactured.

If that is a "Ford type" solenoid, the unconnected post is the "I" terminal which does the job--ballast bypass--that the Mopar ignition switch does. The "I" terminal feeds to coil+ and gives ignition power when starting.

Or it can be "insulated base" and wired as you "think"--where the two small posts are the coil

Or it can be wired (rare) where the coil is internally connected to the big battery post, and the starter button grounds one small post to start (earlier Fords and some tractors/ industrial)

Is this a trunk mount battery? If not you may be well off to "convert" back to the factory starter relay. The key activates the relay, and it activates the starter solenoid. It is also incorporated into the neutral safety switch or 70/ later cars---clutch safety switch.

SO FAR AS gauges---usually pegging guages are a stuck/ defective gauge regulator/ IVR/ voltage limiter. If you do not have a Ralleye cluster, the IVR plugs into the PC board, a small rectangular box.