Where is the pressure control solenoid located; in the transmission. on 2002 Saturn L300

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
My service w/wrench light randomly comes on. Sometimes it shifts hard, sometimes it doesn't. The check engine lights is more frequently coming on with the other light. No one seems to be able to pull a code. My brother read that another owner had the same problem and replaced the control solenoid; it solved his problem.
I was told that to replace it; you just need to remove the filter and it's right behind it. My mechanic claims the transmission has to be dropped to go into the side. Who is right?
(2) Answers
2004 Saturn LW300 . . A tell tale sign the Transmission shift solenoids/ie line pressure solenoids, need to be replaced . . Banging hard into second gear . slipping into 3 gear . . .Also . .Voltage problems in the solenoids/AKA bad solenoids will cause the head lights to be abnormally dim headlights . Indicate need to replace transmissision solenoids . .All electrical transmission componets .2 shift solenoids/Line pressure solenoid/Voltage control plate/2 Speed sensors/and 1 torque converter solenoid . .All seven componets should be replaced when accessed apart . replace all weather needed or not . . .JJ SD Cali . .
your mechanic is right you drop one side of trans down and remove side pan