bad tranny

just over did the tranny and change all solenoid from tranny, have change tranny computer 3 times and the check tranny light come on. At time can run for a day but goes back on flashing again, seems like a bad conection, any suggestion will be appreciated due that during the tranny flashing can read two code, 12,32/any good thoughts will be appreciated for this hillbilly

12 isnt anything to worry about and 32 is an EGR fault code which has nothing to do woth tranny
what is your alternator output voltage with a voltmeter not the guage on the dash