Quote Originally Posted by Chaz View Post
you may have connected the relay the wrong way around. Make sure that the common contact of the relay (30) goes to the solenoid and not the TCU.
You were right. I had terminal 30 feeding power into the TCU, and 87a linked to the lock up solenoid. Can't believe I made such a dumb mistake. After I swapped them over it worked perfectly.

I've damaged the lock up part of the TCU, so now I'll have to manually lock the converter all the time. At least it didn't do any damage inside the transmission, I've had it in and out too many times already.

Having the brake light switch as a cut out for the lock up is really handy. If I was doing it again I might wire it to only work when the system is on. Having the solenoid click every time I touch the brakes was something I hadn't thought about before.

So I owe you big time. First for your efforts with sharing your wiring diagram, and now for guessing what my stupid mistake was. I'm gong to do a full write up of the project, so I'll give you credit in the intro. Thank you.