GM-GMC: heater blower/motor; and where is it???, inner fender, open circuits

Question
1988 GMC 'Burb, diesel, 6.2, 4x4.
The fan, or "blower" stopped abruptly a couple weeks age, and never came back on. We have checked every fuse, wire (for open circuits, or loose connections), torn the dash to smithereens doing this, and couldn't find a problem, and the Chilton's book doesn't have a diagram of the blower motor, or tell you where the heck it even is! We can't check it if we can't  find it. Can you help me locate it? And if you have any other helpful things to try, feel free to let me know!
It's just a bit cold here in oregon to be driving without it, you know?
Thanks so much,
Jennifer

Answer
Jennifer,

I used to live in Washington and I have traveled through Oregon several times.  I understand your comment about the cold.

Chevy and GMC are famous for hiding the blower motor on their vehicles.  In the 60s and 70s, you had to remove the inner fender panel (steel) on the passenger side of the vehicle to get to the motor.

My shop manual is for 1984 and I do not have any information about newer vehicles.  The blower may be on the passenger side of the air conditioner housing in the engine compartment and hidden from view, it may may be inside the air conditioning housing, or it may be behind the glove box.

It will be located on the passenger side of the vehicle.  When you find it, trace its power wire back to the first connector.  That will be on the resistor that controls the blower speed.  Remove the resistor assembly and check to see if it is burned out because this could be the source of all your trouble.