Without Air Conditioning
Battery voltage is applied through the HEATER Fuse to the BLOWER SPEED SELECTOR SWITCH when the ignition switch is in the "ON" position. When the BLOWER SPEED SELECTOR SWITCH is turned to any position but "OFF," battery voltage is applied through the closed contacts in the BLOWER SPEED SELECTOR SWITCH.With the BLOWER SPEED SELECTOR SWITCH in LOW, current must travel the entire length of the resistive element in the BLOWER MOTOR RESISTOR to the BLOWER MOTOR. Since the BLOWER MOTOR is permanently grounded at G201, the BLOWER MOTOR will run at LOW speed.
When the BLOWER SPEED SELECTOR SWITCH is in the M1 position, current passes only partially through the BLOWER MOTOR RESISTOR before reaching the BLOWER MOTOR. Since less of the BLOWER MOTOR RESISTOR is a part of the circuit, the resistance in the circuit is lower, the current is higher, and the BLOWER MOTOR operates at a higher speed.
M2 operation is identical to M1 operation except that even less of the BLOWER MOTOR RESISTOR is in the circuit. Therefore, BLOWER OPERATION in M2 is faster than it is in M1.
With the BLOWER SPEED SELECTOR SWITCH in the HIGH position, the BLOWER MOTOR RESISTOR is bypassed entirely and full current passes directly to the BLOWER MOTOR.