jefftrent

I'm going crazy trying to track down why my OD won't lock up on the highway. Starts at about 45 mph then shutters completely after that. Here's what I've done per the excellent advice served up in this and other forums:

Checked the fluid level
Checked the TV cable (several times)
Changed Brake Switch
Changed TPS
Checked voltage to the TCU
Checked for proper resistance to each of the solenoids at the TCU harness (all around 13+ ohms)
Disconnected the TCU and drove it manually -- all gears shifted fine.
Disconnected the battery to reset the computer and get rid of the P1698 code created by disconnecting the TCU -- I'm now flashing no codes

I have not checked the NSS, but I'm not flashing any CELs or exhibiting any other symptoms that would point me in that direction.

I did see a lot of references to a fuse for the TCU, but I couldn't locate any such beast.

One thought I had is that one or more of the solenoids could be malfunctioning mechanically even though they are getting power and showing proper resistance. Any thoughts or input most appreciated. Thanks!