???? Has anyone ever found the solution for the fluctuating temperature display???

Has anyone ever solved the problem with the fluctuating temepratur indicator?! Did it also mean that they fall from 90C to approx. 70C abruptly when I drive downhill. Sometimes it is not possible?! G62 or G2 Tempsensor I have already changed! Besides that, you don’t go backlight even if I cross the switch. Safety is complete. And my headlight soritzer system doesn’t work?! Does nothing more! Pump is not even running!