radiater fan on when ignition switch is on

If your fan speed increases with RPM increase then you have a stuck fan clutch. One test that you can do to see if stuck is with vehicle off, spin the fan by hand it should spin freely, if it doesn't then can conclude it is a stuck fan clutch

check cooling fan relay underhood for being stuck, replace with a like relay to test. then have it scanned as it may be the cooling fan module bad a mechanic will need to do this.