Ranger 2WD V6-245 4.0L VIN X SFI (1997)
Blower Motor: Testing and Inspection
Open Circuit Test
OPEN CIRCUIT TEST
Electrical circuits are used to control the blower motor.
The heater blower motor switch and heater blower motor switch resistor are connected between the blower motor and ground. Battery voltage is
available at the blower motor whenever the ignition switch is ON.
On all electrical circuits, continuity must exist from the source of power (battery), to the unit where the power is used, and back up to the source of
power (ground). A check at each connection in a circuit, starting at the battery, will locate an open circuit or will show that the circuit is complete.
An ohmmeter or self-powered test light connected at any two points of a circuit with the power removed from the circuit will show if the circuit
between the two connections is open or continuous.
If the meter does not move, or has a slight movement, (high resistance), the circuit may have a poor connection or broken wire. If the bulb does not
light, the circuit is open.
If the meter movement is great or full (low resistance), the circuit is complete. If the bulb lights, the circuit is continuous.
