I have a '93 C1500 with 204K miles that is in excellent condition. Yesterday I ran the AC on high for about 35 minutes while driving home from work. About 20 minutes later I got in the truck and the fan would not come on but the AC compressor was engaged. I drove to the gas station and after filling the tank and starting the engine, the fan was working again.
About three years ago my neighbor was having the same problem in his '92
1500 but his fan almost always "didn't" work. Once-in-a-while it would kick on and run for a while. He bought a new fan controller from the dealer and it didn't fix the problem. We troubleshot the wiring using a multimeter and I think we decided it was a ground problem behind the radio or the glove box but I don't think we ever fixed it completely. I have moved since then.
My friend from work is having a fan problem with his '90 1500. When the fan is running and he turns other accessories on, such as the wipers or headlights, the fan changes speeds or goes off completely.
From what I have gathered from my vast experience with the 9X model 1500's (joking), this fan problem seems to be a common occurance. If anyone has experience with this problem, my friends and I would be forever indebted to you if you could advise us on a fix-action.
Thank you very much! Steven