71 Challenger Wiring Issues

[1mightymopar]

Hey guys, sorry for the long winded post.....hoping some of you can shed some light on a few issues I'm having. I'm in desperate need here. lol I've rewired the car from front to back and installed a rallye cluster. I ordered a ignition harness and turn signal harness from classic industries. The turn signal cam they sent me plugs in ok, but the wire colors are different?? Not sure if it's just a coloring thing or are the wires not in the proper slot causing my issues? Here are some issues I'm having...

1. Where do the 2 red wires go that came out of my old turn signal cam?
2. Is the orange wire for the shift indicator light? Can I just plug that into any orange aux?
3. Tach.. My tach seem to slowly climb to about 1k and stay there or move very slowly. Doesn't go beyond that? Did I hook something wrong or if my tach pooched? Any way to test it?
4. Flasher used to be in a metal holder, hooked into the column. Does that act as a ground or can it stay loose?

Thanks in advance for your help! Greatly appreciated.

 

[Adam]

MyMopar - Mopar Forums & Information - Mopar Wiring Diagrams 1966 to 1971

This link should answer all your questions.

 

[moparleo]

Did you buy factory made harnesses or rig your own. One of the pictures shows a home crimp job on a few wires. Not good. Number one issue on automotive electrical is poor grounds. Every thing must be clean of paint, corrosion or any other coatings. Use a lot of dielectric grease on ALL connections. This seals out moisture and oxygen. This is what allows "oxidation". Which does not conduct electricity. If you make any alterations to the wiring, ideally solder and heat shrink insulate. Year One and M&H harnesses use factory color codes and connectors and so are plug and play. When you mix parts, they are not always compatible.

 

[1mightymopar]

Did you buy factory made harnesses or rig your own. One of the pictures shows a home crimp job on a few wires. Not good. Number one issue on automotive electrical is poor grounds. Every thing must be clean of paint, corrosion or any other coatings. Use a lot of dielectric grease on ALL connections. This seals out moisture and oxygen. This is what allows "oxidation". Which does not conduct electricity. If you make any alterations to the wiring, ideally solder and heat shrink insulate. Year One and M&H harnesses use factory color codes and connectors and so are plug and play. When you mix parts, they are not always compatible.

Thank you. The harness is M&H. The crimped wiring is a aftermarket radio and gauges previous owner installed. I'm in the process of cleaning all that up. Got most issues sorted out expect the tach. Can't figure out why the little movement??

 

[moparleo]

Great. Still, grounds are the root of all electrical evils. And use lots of grease. Have you converted to electronic ignition ? If so, your tach must be modified. The early tachs were not designed for electronic ignitions. Chrysler didn't use them standard until starting in mid 1972. If the dash harness is not for the Rally cluster a few mods are required.

 

[1mightymopar]

That may be my problem. I do have electronic ignition. What mods are needed?

Thanks again for your help.

 

[Adam]

Make sure the white or gray tach wire frame the bulkhead connector is connected to the NEGATIVE side of the coil. I have installed electronic ignition in a 70 and 71 with no mods to the tach, initially; both were later upgraded to the electric board from
RTE 67-74 Tach kit - rte

The kit is easy to install and might be a good save if your tach is toast. I would also recommend the solid state voltage regulator IV3, and quartz clock conversion. This is best done with the cluster out of the car, unless you are a contortionist...jk

But both my cars were originally Rallye dash cars and no under dash wiring mods were needed.

 

[1mightymopar]

Make sure the white or gray tach wire frame the bulkhead connector is connected to the NEGATIVE side of the coil. I have installed electronic ignition in a 70 and 71 with no mods to the tach, initially; both were later upgraded to the electric board from
RTE 67-74 Tach kit - rte

The kit is easy to install and might be a good save if your tach is toast. I would also recommend the solid state voltage regulator IV3, and quartz clock conversion. This is best done with the cluster out of the car, unless you are a contortionist...jk

But both my cars were originally Rallye dash cars and no under dash wiring mods were needed.

My tach may be toast. I actually did install the solid state regulator as well. It dies move to 10k when I start the car and 0 off. So it seems to be getting signal. Strange!! I appreciate the help.

 

[Adam]

The factory tachs were not known for great accuracy, the upgrade should be considered just for that reason.

Good luck!

 

[72RoadRunnerGTX]

I didn’t see these specific questions answered.


“Where do the 2 red wires go that came out of my old turn signal cam?”

The two small red wires are the key in the ignition-switch switch (key-buzzer), they go into position 7 & 8 of the ignition switch connector.


“Is the orange wire for the shift indicator light? Can I just plug that into any orange aux?”

You have a later replacement ignition switch, the small black wire in position 6 (C-body only) needs to be removed from the connector and taped off. The orange wire from your gear shift indicator light goes into that position, should match the orange wire in the dash harness side. Should you power up the headlamps with that small black wire connected that way it will blow the dash light fuse. The small black wire is grounded


“Flasher used to be in a metal holder, hooked into the column. Does that act as a ground or can it stay loose?”

The metal flasher mounting clips are not part of the circuit, they will function hanging loose.