I'm doing a custom install of a 94 LeSabre radio into an '85 El Camino. I have all the wiring figured out except for one wire. There is a seperate Black connector on the back of the radio with two wires- one is ppl/wht, and the other is Dk Grn. I know the ppl/wht goes to the Electronic Climate Control to dim the display, but where does the Dk Grn Wire go? Is it for Steering Wheel Controls? Can I just leave it alone?

Thanks for your help.

If you could please tell us the pin count, like top pins, third from the left, we'll gladly help. One thing you could do is to get an aftermarket head unit adapter and see which wires it says those are.

I've used a schematic from a 94 Roadmaster to verify most of the wires. All of the wires coming form the standard GM radio plugs are accurate and known.
The one that has me slightly stumped is the 7 pin Black Connector shownn in the upper left of this picture.


It has two wires. Pin 3 is the Ppl/Wht, for the Automatic Dimming of the AC control unit. The Dk Green wire is pin 7. Everything I can find suggests it might either be Steering Wheel Controls or maybe Speed Control Volume- Both use Dk Green . In either case, I do not plan to use either of these two functions- just want to make sure I'm not leaving a circuit "Open" that should be attached to something.

Thanks again for your help. The schematics I've got access to just don't go far enough.

Ah, ok I see what you mean. I don't have the same radio setup, but I actually think that'* for an external tape deck. That style of 7-pin plug plays a larger role in Grand Ams with a separate place for a tape drive, though with just two pins, that'* probably for volume and the like. Leaving that open is actually what GM did for a lot of head units where the tape unit or volume controls weren't optioned in.

Thaks for the reply. Guess for now I'll just leave the Grn wire open.

That dark green wire in the 7-pin connector is for E&C (Entertainment & Comfort) Data. It is for steering wheel controls and/or electronic climate control.

Thanks for the reply. That was what I was guessing. Turns out the radio was partially dead, so I'm back to square one anyway.