Radio Wiring

[turbochad]

My factory radio harness on my early 71 T has two wires, a blue one to a single female connector and a yellow/black pair to a single female connector. I know the Yellow/black pair is keyed power, but I was unable to determine what the blue one was for. Any ideas? Thanks in advance
Chad

[evilfij]

If it is the same blue one as on my 1971 911T it is constant power. Of course that could be some random blue wire someone added to mine, but it does have constant power.

Ron

[targatuesday]

Thanks to this thread I was able to find the wires mentioned above hidden way up under the dashboard tucked in above the ventilation controls. Appears to be the same blue wire and the yellow wire with the red stripe. Not sure what the black wire with the home style wire connector is but I will figure that out and deal with it as well. These wires had been cut very short with only about an inch visible but I should be able to test and utilize them. Fingers crossed.

[edmayo]

Pretty sure those were for an optional Webasto. The radio power wire is solid yellow, also tucked back into a sleeve. Most people don't know its there and create all kinds of butchery to wire the radio power.

[targatuesday]

You are correct Ed. I double checked against a wiring diagram and it shows these wires are for the aux. heater. I also found that yellow Radio wire on the diagram and am going to track it down.

I know all about butchered wires in the factory harness. I had to remove the Clifford alarm and Alpine stereo the previous owner had installed sometime in the 1990s. It was a mess of spaghetti and electrical tape beneath the dash.

[targatuesday]

Found the correct yellow wire. Provides 12v to radio when ignition is on. It was inside the same wire sheathing as the power wire for the ashtray light. Yellow wire was not visible, it was inside the sheath maybe 1/2”. Hopefully this info will help someone else.

Also, I looked at the wiring diagram again and it appeared the black wire that is part of the trio of wires for the auxiliary heater should be hot when the ignition is on. Tested it and sure enough, 12v when key is switched on. I did not tap into or use this wire but this info may prove useful for someone reading this thread someday.