Hi there. I seem to be having a problem with my fan blower where when I go through the speeds of the speed control knob it doesnt work at all. I am going to buy this part tomarow to replace but wanted to know if its not what needs replacing. when i drive and press the gas pedal hard the fan seems to come on and as i let go of the gas pedal it turns off again. could this be the resistor or is it definately the fan. cheers