HI CAN SOME ONE HELP I HAVE 2002 FORD KA 1.3 I HAVE A PROBLEM WITH A HEATER BLOWER IN SIDE THE CAR IT ONLY BLOWS ON NUMBER 4 SETTING OF FAN SWITCH DOES NOT WORK ON 123 SOME ONE HAS TOLD ME IT COULD BE A RESISTOR IF THERE IS SUCH A THING WHERE IS IT SITUATED IN THE CAR PLEASE HELP