my vw polo is overheating...
its gets to 115 degrees celcius and the thermo fan does not operate. the fan works because ive put direct power to it. ive replaced the thermo fan switch in the radiator with a brand new one and the fan still does not operate.
not sure if this is the problem though but would like to at least fix this...
can anyone help me???

Have you checked to make sure there's power to the switch.

The fuse could be blown or the relay gone bad.

yeh put power to the switch, fan operated...
all fuses are ok, where abouts is the relay?

Did you just run power from the battery to the switch?
If so that might be the problem, the car might not be suppyling power to the thermo switch.

Do the fans come on when you put the A/C on?

It may not have a relay, some cars do some dont, most that use a thermoswitch in bottom of the radiator to trigger then fans don't usually but if its got one it will be in the engine bay fusebox.