P0745 2004 Nissan Sentra 1.8 how to fix.

Question

I changed fluid and stuff. still shifting hard, mainly trying to figure out if I took the pan off what am I looking for. want to get it fixed before its too late.

Answer 1

I would drain the fluid in a clean bucket and check to see if there is metal debris also remove the transmission pan and see if the magnet has a lot of metal stuck to it. if it does the tranmission along with the valve body might be bad. If its clean I would refill with the Nissan fluid and see what happens. 

also the dropping resistor could be the issue it is near the battery, cant find an exact picture 

if the car is shifting hard you might already be late (in many cases)

if you see alot metal pieces it is probably from the gears grinding and the transmission will need to be replaced.