Ho,

I looked at the blower fan wiring.

Everything involved is just behind the glovebox to the right of the radio
and to the right A post, which needs the trim removed where the passengers
right knee and lower leg are.

You could expose the ground branch point there, and look for loose or fallen off black wires. Try wiggling the wires from the heater with the two wire connector.
see if the heater fires up when you tug on those wires.

A meter can verify that you have power at the motor connector.

Post back

Bill