No easy way w/o a OEM wiring manual handy as there's several wires in two plugs going to that resistor unit. Checking for voltage at the blower motor however isn't that difficult.

Do you have any climate system fault codes stored in B1, flashing LEDs on face of climate unit when car's first started? That's the first thing you should check.

To test your blower motor, you'll first need to get the knee bolster removed, 3 nuts and remove the lower r. dash screw which'll help as you can then move that corner of the dash just enough to easily remove the knee bolster.

You'll need a test light or VOM to check for voltage at the blower motor. If you have a 12 v circuit there and it's not working, the blower motor is NG. If you don't have 12 volts there, then your problem lies elsewhere like "possibly" the resistor unit providing that no other fault codes for sensors, etc exist. If certain fault codes exist, the control unit shuts off the blower motor.