2001 Chevy s10 blower will not work on high

On my s10 blazer 1992 the switch only worked on low then I replaced the switch and all settings worked fine for about 2 years now the switch only works on hi, but I replaced the actual switch on the dash to fix mine as the blower was fine. Now I just use hi as before low was to low and put a new switch in but hi is what i want anyway so if hi stops I have a replacement from pull-a-part ready to go in the glove box. I think the gm switches are problematic.

Thanks for the info on replacing the switch from what you said though it sounds like you need a new resistor

I will check that, thanks