heater

Note the diagram for front blower motor. See the blower motor wiring connector, take it loose from blower motor, use both ends of test light at those two terminals, key on, blower motor controls on. If test lamp comes on, you have voltage and ground and I suspect the blower motor itself is faulty. If the lamp doesn't come on, your missing either voltage or ground, which one? At the blower motor in diagram, top purple wire is voltage. Bottom black wire is ground, check them both.