I've always been irked that the transmission on Ford products defaults to Overdrive being activated. Since it's not a good idea to let your transmission be hunting back and forth between direct and overdrive while you drive around town, I try and remember to shut it off. However, I usually forget until it shifts into overdrive the first time...then I go "Doh!". I've always thought it dumb you couldn't switch the default around. So today, I did just that...kinda...
First thing I did was build me a circuit with a 555 timer and my breadboard. Although it was fun, getting it all onto a circuit board was going to leave me with a rather large electronics piece. I may be able to design and built the circuits, but making them small and usable isn't my cup of tea. All thumbs I guess!
So I looked up on pegboard and found a couple of TR7 modules there. Perfect! So I programed one up to Feature 17, and wired it up. By the way, Feature 17 isn't on any instruction sheet. You need to go to PAC's website and find it. They won't support it either...but it's still there and very usable. Let me know if anyone wants to try this and needs the programming instructions.
Anyway...here's the module in the first picture after I soldered the supply and trigger wires together. I want it to trigger a pulse 3 seconds after the key is turned on. This does that. It pulses down the blue wire. The shrink wrap on the blue wire is for a diode to prevent 12V from going back into the module when I manually trigger the factory switch. I'm not sure you need this...but it didn't hurt.
Then you go under your steering column. Remove the lower panel and support for access. find the small connector from the OD switch. It's to the side of my finger in this horrible picture. (2nd picture) There are two wires to this connector and you need to tap into each of them.
The Violet with Orange stripe is the power line. It's hot in run. Tap your red lead into this wire. The other wire is Tan with a White stripe. This goes to the ECM and tells the ECM to toggle the OD feature on and off. Tap your blue wire into this wire. Solder an appropriate end to the black wire and fasten it to the green ground bolt to the right of the steering column. Fasten the TR7 module out of the way and your done. (last picture)
Now, everytime I start the car, in 3 seconds, the OD light turns on and I default to no overdrive. The factory switch on the end of the stalk still operates as normal. Just a little something to do on a slow day!
By the way...I have an $800 Fluke meter that does a LOT. But I haven't had it out of the case in months now. I keep fishing out this cheap Walmart meter you see. I think it cost me all of about $10. I bought it when I needed it at my son's house one day and we didn't have one. I use the hell out of it! And I just toss it in the tool box. I don't treat it nice at all. Had it for about 3 years now. EVERYONE needs a meter...and this is about as cheap as it gets. And it works! (if I need very precise measurements, I get the Fluke out...but this one is good enough for 99.9% of your needs)