So I have a 2006 gs 430 and I got a check engine light I used my scanner and it's a code for shift solenoid c I've read on the forums that usually the car won't shift past a certain gear but its seems to be shifting into all gears the car did start to shift slowly in that I can't floor it and accelerate quickly, I plan on removing the pan and testing the resistance of all the solenoids and I might as well change the filter and obviously the fluid but I'd like to know if anyone has had this problem and how they fixed it or how they diagnosed the problem since I don't want to just throw parts at it.​​​​

 

Have you ever replaced the fluid previously? If not could be gunked up