H & M Rallye Harness problems

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Uncle Ben

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Hey guys, I've installed a brand new harness from Year One (h&m electric) in my 1971 Dodge Demon and it has the rallye cluster. The issue is when I turn the key on the dash lights come on and cannot be dimmed.

If you unplug the accessory circuit it works as normal and you can dim the lights.

I've read that the Orange wire that goes to the key is the Acc. circuit but it seems that is hooked up to the lights as well?

I also have no power to my gauges at all so the only one working is the ammeter. Anybody have this issue? I've looked all through the FSM and seen nothing weird or strange in this harness, but I cant for the life of me figure out what's all out of whack.

side note, the car did not originally have a rallye culster in it but I installed a 68 Cuda dash with key on dash and wired the Key JUST AS IT WAS in the Original Column.
 
From 68 cuda to 71 demon, I can almost guarantee some changes. Best to get factory wiring diagrams for both years and compare.
 
Dash harness? If so when I did my 71 Demon rally dash all harness’s were replaced, I rang and checked everything. I found 2 wires at the bulkhead connector swapped on the under dash harness. I can’t recall which, it’s been almost 5 years. Check all the circuits with volt/ohm meter per wiring diagram.
 
UPDATE: i found out that since the car was originally a column shift car it had a light in the column for the PRNDL facia :BangHead: i feel dumb. So that orange should be there if you have that. So now i need to figure out which one of these other wires is the Acc. I see that theres two black wires into the same pin on the column plug but they dont have continuity to any of the fuses? Also i have a black “Hot” thats on the last pin next to it that goes to nothing on my connector. So confusing.
 
Do a search here for dash light circuits. They're on their own circuit starting at the headlight switch.
 
The rally panel has 2 switched hot wires going to it. One powers the brake warning lamp. The other powers the gauge voltage limiter inside that fuel gauge. Some standard panels had only one switched hot that powered brake warning lamp, oil warning lamp, and the plug in type voltage limiter.
These switched hot wires were not fused other than the main fusible link before ignition switch.
 
The rally panel has 2 switched hot wires going to it. One powers the brake warning lamp. The other powers the gauge voltage limiter inside that fuel gauge.

Swapped the gauges out for licensed mopar restoration gauges that use a solid state limiter. The new fuel gauge has no IVR points
 
They are only hot with key in run or accessory positions.
Keyed Accessory is pretty much everything not vital to running the engine.

Did you look at the top diagram I linked to? That should help
 
UPDATE: Guys thanks for all the help! I went back and read some old forums and realized what i had done. The large black wire is the acc. Circuit not the ground. Oops. Everything is working!
 
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