Well I sat down and thought about the wiring for the TC switch, and thought about needing to have the PCM flashed. I won't be able to have the flash done for a while, so I thought about the wiring and what I could do about it. Well i came up with a wiring schematic that retains the original relay but bypasses it when the TC lockup switch is thrown. Basically I used a total of 4 relays (including the original and one to allow brake light shutoff of the TC). I don't have any way to draw up the diagram on my laptop right now, but I'll post it when I have time. Basically relay 1 is the original trans relay, mounted remotely from the distribution box. 3 of the relay's terminals are wired directly to the dist. box and the 4th is run to terminal 87A of the second relay. A wire is run from terminal 87 of relay 2 to the dist. box, and terminal 86? (the other output wire from relay 2) is connected directly to relay 1. What this does is allow use of the original trans relay when the switch is off, and the relay is bypassed and the proper jumpers are made in the dist. box when relay 2 is powered.

Relay 3 is wired in parallel with relay 2 from the switch, so the switch operates both of them at the same time. Relay 3 grounds the TC wire from the PCM, as the basic TC switch would do.

Relay 4 is mounted inline to the power wire feeding relay 2 and 3, shutting off the power when the brake lights come on.

The switch on the dash just grounds relays 2 and 3. I know it sounds complicated without pictures, but its actually a pretty clean install. I have all 4 relays mounted beside the dist. box where there is plenty of room. 1 power wire getting power from the dist. box feed wire, 1 ground, wire running to the switch, 1 wire to the brake light switch (I didn't hook that one up yet), and 1 wire to the PCM.

I tested it out and was thrilled that the TC worked as it should with the switch off. Step 1 completed! I threw the switch and it locked right up. Cool! Step 2 down! I flipped the switch back, which is where things went wrong with the basic 1-wire TC switch, and....the TC unlocked!!! Sweeeeet. O.K., I was riding on a pretty good high at that point....

...and then. I flipped the switch and locked the TC and hit the OD button...and nothing happened. Hmmmm. I flipped the switch off and the trans immediately shifted out of OD and stayed there, but the OD switch wasn't lit. Hmmm. I pushed the OD switch and nothing. I flipped the TC switch again, and it shifted to OD and locked up. Strange. I pulled over, shut the truck off, and restarted it and took off. The OD switch worked fine now. I flipped the TC switch and tried the OD switch, and it again didn't work. Really wierd.

O.K., I now have a greatly improved system, but its still not perfect. Any suggestions from the wiring whizzards who know this circuit better than I do? i know thats a lot to ask without a diagram to show you exactly what I did...but I'm hoping I get lucky.

Jim