Chevrolet Repair: 98 K2500 heater, chevy k2500, contects

Question
Tom, my 98 Chevy K2500 has keeps going thru resistors for the heater blower motor which in turn burns out the fan switch, so both must be replaced at the same time. Replacements may last from a week to a year and i can not locate any wiring shorts or hot spots that may be the source of the problem. I have also replaced the relay next to the resistor and this seems to have no effect on longevity. Any clue as to what I maybe over looking?

Answer
HI DANIEL,YUP, THIS IS A PROBLEM..MY 2005 WAS UNDER RECALL WARRNATY,SAME ISSUE..WHAT IS HAPPENING IS THE RESISTOR GETS WARM AND HEATS UP THE CONNECTOR PLUG TO THE RESISTOR CAUSING IT TO ARC..ONCE THIS HAPPENS THE CONTECTS GET LOOSE CUASING IT TO HAPPEN MORE OFTEN..WHAT GM IS TELLING US TO DO IS REPLACE THE RESISTOR WITH A UPDATED ONE AND ALSO REPLACE THE HARNESS CONNECTOR,,NOT CHEAP.[CONNECTOR ABOUT $95.00] WOULD SUGGEST USING GM PARTS ONLY.[[THERE IS A TSB ON THIS[TECH SERVICE BULLITIN]]..HAVE YOU LOOKED AT THE CONNECTOR TO SEE IF THERE IS ANY BURNING GOING ON ??? WE HAVE REPLACED MANY OF THESE.