Ok really appreciate all the help! Now let's just theorise for a moment and assume the fan does work at all speeds and the reason the previous owner decided to bypass the system was purely based on the fact that the temp gauge "indicated" the fan wasn't running when in fact the engine temp was simply below 97 but the gauge showed the motor was getting really hot??? (his bypass was simply a single wire from 12v to the relay coil so when you turn ignition on the fan runs full speed and all the time) At the moment I just have my dash switch in that 12v line so I can switch the relay on and off. Now, is there any way to "test" that the fan does work in slow speed (we already know it runs at high speed) otherwise would it doe any harm to run the engine on idle and monitor the physical temperature (maybe take reading off the brass base of the temp sensor where it screws into the thermostat plastic housing?) and the slow fan should kick in at 97 correct? then the full speed fan should kick in at 110 ... I really don't think I have ever had the engine temps at that level as I switch in the fan at an "indicated" 100 which in actual temperature would be much lower. The highest temp that has coolant running inside seems to be the area around the temp sensor and it's both new and working. Obviously for that test I would have the fan bypass disabled What do you think ???