Wiring Questions

[74 DART']

I have a couple of wiring questions on my 74 dart. Ive been working on fixing some of the dash wiring. I have the factory am radio, does anyone know what the radiuo uses for a ground? I have a red and orange wire connector, and i found the connector under the dash for this, one must be power and the other for illumination to the radio. The other wires coming from the radio are one black and one green , i assume these run up to the speaker. The orange and red connector was looped together by the previous owner, when i disconnect this and hook it back up to the radio i loose my dash illum lights. When i hook the loop back up my dash lights stay on anytime the key is on. Anyone have any ideas on this. I also found a black with white stripe (ground wire)? attached to the dash under the ashtray but i cant find where it should hook up to. The radio maybe? Thanks in advance J.R.

 

[RedFish]

The radio is chassis grounded like most of the rest of the car.
Orange is radio dial lamp and red is radio power. To loop the 2 would feed back all the way to headlight switch lighting all dash lights in that path since those are chassis ground also. I dont recall black w/ white tracer.

 

[RedFish]

If you cant get dash lights on from the correct power source the dimmer reostat in your headlight switch is probably toast. Fairly common failure.
While most just buy a new switch, I choose to bypass that reostat at the headlight switch and get bright as possible lighting regardless of knobs turned position.

 

[74 DART']

Thanks, yeah i think my headlight switch is toast, ill change that soon, was just wondering if the radio should have a ground wire, that black wire could have been added by some where along the line. There's been alot of hacks in there and im trying fix that. Thanks for the input. Im sure ill have more questions along the way!