Early 911 radio wiring question...

[dotorg]

This has been driving me nuts since I bought this car... I seem to be able to wire up my radio to either work with the car on, or with the car off, but not both in the "accessory" position and "on" position.

Looking at this wiring diagram, which seems to match my 911L diagram in the manual, it shows a red/white wire coming off the key switch and running to the radio.

If you trace that wire, you see it goes through a diode, and crosses a red wire with a white square on it. Does that mean these should be connected? Where does this bank of diodes live? There are no red/white wires under my dash -- clearly someone who thought they knew electronics had their hands on the car cut it out at some point. I've got no idea if its replaced with a different color, or just not there.

There are six tabs coming off the back of the key switch. When I got the car it had a radio "installed" (but not working), which seemed to be getting power from the center post on the key switch. Its the only thing wired to that post. With my radio wired to that, it works with the car on, but not in the "radio/acc" position on the key.

So here's my questions, specifically for those who are an expert on early 911 wiring, or those who have a digital camera and can take some pictures.

1) What do you have wired to each of the tabs on the back of the key switch? The radio wire is on #79 in that diagram, any idea which one that is?

2) Where does your radio lead go from there? Does it go under the dash to the radio, or does it go into the wiring harness? I've got a red/white wire in the trunk, which actually has a burned hole in the insulation(!!!) which doesn't ever seem to have power. Perhaps thats why it all got ripped out? (Actually looking at the diagram, that might be something with the headlights, which I didn't flip on when I was testing it...)

I figure I can get a couple of reasonably sized diodes and wire up my own power source if things are so messed up that I can't reconstitute the original wiring, but I need to find where I can get that "radio/acc" power.

Any tips/suggestions/help are greatly appreciated. This is driving me nuts.

[Peterfrans]

that's no diode, its a multi connector behind the dash. There should be a red/white wire hanging loose around somewhere down there.

[Early_S_Man]

dotorg,

The Red/White wire coming off the ignition switch doesn't have a diode inline, and isn't connected to any other wire! It goes thru a multi-pole connector (8 pins) but it passes underneath the Red wire in question with white square that goes through the same 8-pin connector.

[dotorg]

Ah, okay... Any idea which connector on the back of the key switch it should be hooked to? The red/white in the trunk might be the radio wire after all, but its definitely not wired to the switch...