This is a slightly-improved version of a diagram I made when I built my Bronco. It now has the ~'01 C234 pinout in the lower L corner.
IF THE IMAGE IS TOO SMALL, click it.

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The EVTM is amazingly wrong & incomplete, so I had to disassemble the wheel & pull the clock spring back out of my column to create this diagram. I'm trying to program the EATC buttons to work my KDC-X997 via a SWI-RC, but they're on a separate output wire (W/LB) not shown in the original Ford EVTM (which is why I couldn't put a circuit number on it).

The codes beneath the wire names in the photo indicate which internal steering wheel connectors that wire goes to:
A=Airbag horn switch
2=L&R
3=L&R&Airbag horn switch
The wire at the far R of the connector that looks gray is actually LB/Bk.

The resistance values for the cruise switches are correct. But those for the radio/EATC are technically wrong. They're values I measured from the ground pin to the output wire, so the only values that MIGHT be correct are the parallel resistors shown for each output. The values shown by the switch positions are the net resistance for the parallel resistor plus the switch resistor.

I also measured resistance again with the 2 output circuits shorted, and those values are:
none . . . . . . . 2370
NEXT . . . . . . . 406
MODE . . . . . . . 752
VOL^ . . . . . . . 199
VOLv . . . . . . . 74
TEMP^ . . . . . . 333
TEMPv . . . . . 1265
FAN^ . . . . . . 671
FANv . . . . . . 128

Since none are close to another, I hope the SWI-RC can use all those values, giving me 8 buttons instead of 4.

**UPDATE** Turns out the SWI modules CAN'T learn the HVAC buttons. But most modern touch-screen radios CAN.

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SEE THE NEXT PIC...

Owner caption December 2015 · Photo 965 of 980