Overdrive switch does not work

2002 Windstar. The overdrive switch does not turn on the "OD off" light on the dash nor does is shift the transmission down. The transmission is otherwise working normally and it does shift down automatically when going up a hill.
I have pulled the OD switch connector under the dash and verified the switch is working with an ohm meter. I have pulled the dash display out and verified the lilght bulb is good. Is there a schematic available for this circuit? Any other ideas? I am afraid I am looking at the power train control computer. Expensive!

check to make sure you have 12vdc on the red/yellow wire coming into the trans control switch TCS. If you do, then check for resistance between TCS pin 2 (light blue/yellow) harness and the instrument cluster pin 21. If the resistance is less than 5 ohms, you have a cluster problem. If greater than 5 ohms, wiring is ok. The O/D is cancelled through the instrument cluster.

Instrument cluster pin 21. Is that on J1? I see the pin 1 locater, do I just count to the right from there and include or exclude the two larger offset pins?

OK, I took my glasses off and now I see the pin numbers. J1 has 3 separate plugs. The two outside plugs are numbered 1 - 22, the middle plug is numbered 1 - 20.

OK. The 12v check showed the problem (no 12v). Would you believe I pulled all this apart to diagnose a blown F14. Next time I will not have my wife look up the fuses.... Hopefully it was a fluke, otherwise the big question is what blew the fuse??? Its working OK for now.

Thanks for the assist!

Craig

Craig,

If you would have told me that your wife checked the fuses, I would have ... . ... .oh wait, I'd better not go there. That kind of talk always gets me into trouble. Just glad it all worked out for you without major $$$$$$.