how can i fix my fan? Transit smiley face 's' reg?

Hi, 2.5l diesel 1996 non turbo transit, the heater blower fan 1 and 2 speed has packed up, leaving just 3rd speed only, have taken the 3 pin block connector off the resistor behind the headlight, cleaned the spade connectors and sprayed wd40 into block connector, still no joy! is there anything else to check please? thanks in advance.