Hello! I'm new here but not to tuning. I used to post of thirdgen about 15 years ago (holy crap I'm gettin old). I had small blocks in Astro vans. I read a lot of the threads and some familiar names popped up

Anyway I just bought a 95 K2500 7.4 / 4L80E truck. Needs some work. Main issue is the TCC won't lock at all with codes 68 and 83. I checked the usual things fuses and whatnot. I borrowed a Tech II from a friend and found the TCC works if I command it it. It just doesn't by itself. Brake switch status is good. ISS and OSS, TRS all look fine. I should note that the knock sensor is broken and the O2 isn't in (bung rusted away). I'm waiting on the mail for replacement parts.

I'm here asking "what gives" because if this were a 7747 a fella like RBob could say wether or not the missing inputs would case the TCC to flake out.

Thanks for any advice