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An easier way to see if the fans work is remove the left forward console panel that is held by the two screws holding the black plastic heater vent. Use this picture to locate the relays mentioned below. Muttony, who is one of the members, wrote a very detailed and useful post (link below) on trouble-shooting HVAC problems.
"The point of all this is that there should be 12V battery power at the relay regardless of key position at post 30/51 which is the post in the middle with the screw and the Brown and White Wire. As seen on the diagram, power goes from post 2H via a Green and Slate wire directly to the fans.
Verifying the fans function is simply a matter of jumping the Brown & White to the Green & Slate. If the fans come on, then the fault is elsewhere. In my case, doing this caused the fans to come on so Gummed Up fans was ruled out."
there are two blower fans, each enclosed in a blower case, one driver side, one passenger side.
There is a green wire and black wire marine connector on each side entering the blower cases corners near the kick panels.
Disconnect these connectors and using a spare battery with two wires, positive pole to green wire, negative to black wire, you can test each blower.
otherwise the problem might he the large relay explained by Dave above.