The engine C1850 Code is information of the car engine problem and this trouble code helps the car engineer to solve the car engine issue. Do not allow different meaning of the car engine. Do not use automobile meaning of the car engine code what you will get from online. C1850 OBD 2 code on car with electronically mainted automatic shows, the 3-4 shift solenoid is accountable for activating the hydraulic circuits to trigger clutches or bands that alteration gears inside the automatic spread. Solving this problem from the car engine is not very difficult and it is not necessary to change any component from engine.