I have a 90 c1500 that the ac blower that would sporadically work. I replaced the blower and had no problems for about a week. It then too stopped blowing all together. I then replaced the blower resistor and still no go. I then swapped the relays off my bosses identical truck and still nothing. I dont think its the control panel cause i can hear the relays switching. I also tried wiggling the connectors gently to see if possibly the connectors were loose. Any advice is greatly appreciated, im not enjoying this fl summer heat without my ac!

 

Have u checked for power down by the blower motor or resistor?

 

tested for power at the blower motor and didnt find nothing. that was before i switched out the resistor. i also checked fuses and they are fine. ill check for power at the resistor. if there is none, whats the culprit?