Prizm L4-1800cc 1.8L DOHC (1993)
Radiator Cooling Fan Motor: Description and Operation
RADIATOR FAN MOTOR OPERATION WITH A/C SYSTEM OFF AND RADIATOR FAN MOTOR OPERATION WITHOUT AIR
CONDITIONING
The Radiator Fan Motor will operate at full speed when ECT reaches 90°C (194°F). With the Ignition Switch in "ON" or "START," voltage is
applied to the coils of the ENGINE MAIN Relay and the FAN NO. 1 Relay. Since the ENGINE MAIN Relay is permanently grounded at G102, it
energizes. When ECT reaches 90°C (194°F), the Fan Thermostat Switch opens and ground is lost to the coil of the FAN NO. 1 Relay. FAN NO. 1
Relay deenergizes and voltage flows through the closed contacts of the ENGINE MAIN Relay and the FAN NO. 1 Relay to the Radiator Fan
Motor.
Since the Radiator Fan Motor is grounded at G102, it runs at full speed. When ECT reaches 83°C (181°F), the Fan Thermostat Switch closes, thus
providing a ground to the FAN NO. 1 Relay. With this ground provided the relay energizes. With the relay energized, the current path to the
Radiator Fan Motor is interrupted. It is when this happens that the Radiator Fan Motor will stop running. The Radiator Fan Motor will cycle ON
and OFF at full speed as the ECT increases and decreases.
