senor honda

The blower motor resistor has multiple resistor wires, each of which will reduce the current flow through the blower motor to change the blower motor speed.
The blower motor switch in the MTC heating-A/C system directs the ground path for the blower motor through the correct resistor wire to obtain the selected speed. With the blower motor control in the lowest speed position, the ground path for the blower motor is applied through all of the resistor wires. Each higher speed selected with the blower motor control applies the blower motor ground path through fewer of the resistor wires, increasing the blower motor speed.

I don't know how common it is for the blower motor resistor to fail versus the blower motor.
You can test the blower motor resistor using the following procedure:
1. Disconnect and isolate the negative battery cable (main battery).
2. Disconnect the wire harness connector from the blower motor resistor
3. Check for continuity between each of the blower motor switch input terminals, of the blower motor resistor, and the resistor output terminal. In each case there should be continuity.
If no continuity, replace the blower motor resistor.
If there is continuity, the blower motor resistor is good. You can then check the wire harness circuits for the blower motor switch and the blower motor.

Caution: Do not operate the blower motor with the blower motor resistor removed from the circuit. Failure to take this precaution can result in vehicle damage.