heater fan switch quit working 2001 Century. not a fuse problem. any ideas?

It could be that you have a bad blower speed switch (on panel below radio), or a bad blower motor. Remove the speed switch from the dash (leave wiring harness on) and while the ignition key is in the "on" position, test (with a multi-meter set on DC) for 12V voltage at the blue, yellow, and tan wire connections. If no voltage is detected, then check for continuity between the brown wire in the wiring harness and each of the other wire terminal connections on the back of the switch, as the switch is run through its speed selections. If still no voltage, the switch is your culprit, otherwise switch your focus to the blower motor. If the blower motor is found to be defective, it should be replaced as a set with the blower motor resistor.

I just replaced the fan speed switch on my 2004 Century,the switch and the plug were melted. I replaced the motor and resistor first but still did not work.