!Alert! - newbie AND blond (ish) female!

1996 Audi A4 Avant 1.8 - green.

Within seconds of start up the coolant/temp red symbol starts flashing and does not go off. I've read the book and the coolant level is fine and the fan behind the radiator is working. Whilst driving, the temp gauge remains between 60 and 90. So methinks it's not overheating nor losing coolant/water and having read numerous posts on here it's probably the sensor in the little plastic tank. The only thing that I have noticed is there is 'steam' coming out of the exhaust.

If you all agree that it is a faulty sensor could I (here comes the blonde bit) just cut that wire that comes out of the bottom of the plastic tank to stop the warning light coming on?

Thanks for reading.

Steph x