Mitsubishi Repair: Fto Fan, mitsubishi fto gr, engine coolant temperature

Question
Hi Anthony,
I own a 1995 Mitsubishi fto gr and at the moment the fan doesn't turn on ... the fan has been tested to make sure it works and it does .... the car runs until the gearbox overheats and then locks in 3rd gear ....  i was just wondering whether you may have an idea of what could cause the fan not to turn on when it reaches running temperature

Answer
Robert,
I'm not familiar with your particular car, but in general, there are coolant temperature sensors that monitors the engine coolant temperature.  There is at least one sensor near the thermostat housing and usually another sensor attached to the bottom of the radiator.  When the sensor detects the coolant has reached a specific temperature, the fluid is allowed to flow through the radiator and fan(s) can come on to help maintain a constant running temperature.

Have your thermostat and sensors checked to start with.  Else, there could be a problem with your water pump or potentially your car's computer is faulty.
Good luck!