I have a 2008 mazda 6 2.3l. I am getting P0841 on my scan tool. In 2019 I changed the transmission fluid because of rough shifting. I did not use the recommended fluid. 2021 I changed the transmission fluid to mazda m5 but I didn't change the filter. I cleared the code and the code came back. I am not experiencing any hard shifting and the gears starts off in 1. For the code to clear should I change the filter? Also should I change the tfps switch? If I have to change the switch is the switch internal or external? Where is the switch located?