95 Blazer S10 4wd 2 door - The blower does not turn on all the time. When the car starts sometimes the blower goes on and sometimes it doesnt - when the blower does go on it works fine, air blows and at the different speeds. When it doesnt work, it doesnt work at all.

A couple of times I started the car and the blower would not work. After driving a couple of miles it would mysteriously come on and work fine for the balance of the trip. I know the three main components are motor, relay and switch - each of which are difficult to get to to replace - cut them out of the blower box or disassemble the dash to get to the switch.

Any help on diagnostics or another part lead would be appreciated

 

I had the same thing with my 91 jimmy.Turned out to be the motor. After you start your truck if the blower motor don't start , take a metal rod and tapp on the motor casing, if it then go it's your blower motor .