2002 Seat Alhambra petrol rad fan issues

[gafo]

Howdy folks, newbie here ,well Alhambra newbie . I've had an Inca and I have a m.k 1 Golf G60.. Maybe go to Introductions after this. Anyhoo ,I have a 1997 Alhambra TDI. Good strong engine ,Bodywork not one of its strong points.I also bought a 2002 Alhambra that has the petrol ATM engine ,I was going to cut the sill out of this for the diesel . But this is in great cond .with 97k miles ,problem is the rad fans dont come on and the temp is going to 120 dg before I turn engine off. I replaced Coolant temp sensor, the thermostat also replaced the thermoswitch.Ive checked the rad fans and they work Ive bridged the wiring to the Thermoswitch and the fans come on. The temp gauge goes to 120 and then it resets to zero.Then when I turn engine off and restart it the oil light/buzzer comes on and the temp gauge is in the red .What am I missing here?I hope Somebody can advise me. Thanks Ger

[gafo]

Bueller, Bueller anybody?