Challenger wiring experts ?

car is a 70 SE with Rallye dash. It's been 7 years since I took it apart and of course I didn't properly document what was connected where. I've been looking in the FSM and so far have struck out. First wire in question is just forward of the passenger door, 3 pin connector with 4 wires. 2 yellow with black trace, 1 red and 1 dark blue with white trace. Where does this go?

That socket connects to a 2983872 key in ignition buzzer relay. It bolts to the bottom dash frame and right beside it should be a 2983336 low full relay for the SE/GC e bodies.

Jim

many thanks! Now the second one. 2 wire connector with yellow and dark blue with white trace. Lamp is fed by a yellow wire.

No problem at all. This second picture seems to be showing two different unrelated parts. The bulb fixture is called a title light that works from your delay lighting sub harness. That mounts on your gauge cluster light bar on the far left to light the switch panel. The five sided connector is part of the low fuel relay wiring.

Jim

and this is the low fuel relay, right?

That's correct.

Jim

one more wiring question. Solid dark blue wire behind gauge cluster. It's not my fuel gauge becuase I just found that and fixed it last night. My tach works so it's not that. Any other dark blue with no trace back there?

I'm not an expert but if that blue wire is on one of the posts for the ammeter gauge I believe it should not be there.

It's either is for the fuel, temp or oil gauges

Pretty sure on this.

I'm sure an expert will chime in.

Bill

If we all turn to page 8-94 of our FSM

The Dark blue with tracer & Black socket go to the Brake lamp.

The Blue wire either goes to the fuel gauge or the tach - it goes not go on the ammeter

Blue is fuel
Purple is temp
Gray is oil

Just looked at a complete,dash out of the car, 1970

Then I thought for a second, same colors that go to the sending units.

What color wire is to your fuel gauge?

This is the tricky part with wiring on an SE - GC. The voltage limiter at the cluster powers a normal non rallye fuel and temperature gauges and the rallye cluster fuel, temperature and oil pressure gauges.

What is different with the SE - GC the fuel gauge does not use the voltage limiter for power, but with power from the low fuel relay. So, the normal dark blue wire from the fuel sender through the rear wiring harness connects to the DB terminal on the fuel gauge. Then there is a second identical dark blue wire from your low fuel relay mounted on the passenger side dash near the key-in buzzer relay that connects to the power input side of the fuel gauge.

The low fuel relay is a two circuit device driven both by heat. One circuit creating the pulsing voltage for powering the gauge and the second is the monitoring side of the fuel sending impedance to be able to light the low fuel bulb in the overhead console.

The picture of the internal circuit board shows these two contact points. The heat from the coil wrapped on the arm of the low fuel light contact would arc the arm away from it's resting point to keep from lighting the bulb between a full tank to just under a quarter tank. The heat from the coil wrapped on the arm of the pulsed voltage gauge contact would do just that. Warm and pull away, cool and make contact, on and off about every second.

I hope that clears up the SE - GC fuel wiring or is as clear as mud.









Jim

Jim, that makes perfect sense! Thanks again