Have had a lexus is250 rwd for couple years, started noticing transmission not going into reverse when it was cold so I changed trans fluid after that car completely stopped going into reverse no codes or anything techstream showed normal behavior of shift status, the car would launch forward in park till it hit the pin, move forward in neutral but wouldn't shift above 1st and reverse acted like park drive mode worked fine but i did notice no engine braking when i down shifted in sport mode. decided to swap the valve body with all new solenoids and it made no difference. decided to pull a whole new transmission from a working unit with 80k miles on it swapped it last week and still made no difference. Have worked a lot on this car would love to get it running again. All the wiring to the transmission has been checked for continuity. After swapping the new trans techstream shows a code for yaw rate sensor.

Any help is greatly appreciated.