ST204 Transmission problems!

[ROAMER79]

Hi guys! Nice to see such a big Toyota forum going on!!!

I have 1995 ST-204 Celica. Recently I'm having problems with transmission downshifting from 4th gear or two, and then returning to normal (4th gear) for no apparent reason.

I have checked electrical control system as far as much as I could and everything seems to be OK. I'm not getting any error codes. Didn't check solenoids for clicking as I couldn't figure out connections and pins. Checked the cable, it's OK too.

Only thing that is not "by the book" is TT terminal voltage on the diagnostic terminal which is supposed to go to 6Volts as throttle opens, in my case it goes to 8.2 when throttle fully open.

Anyone had similar problems? Or any advice? Many thanx in advance!!!