Radiator Cooling Fan: Description and Operation

1. FAN MOTOR OPERATION
When the Ignition SW is turned ON. current from the ECU-IG fuse flows to the Fan Relay No.1 (Coil Side) and the Fan Relay No.2 (Coil Side) --> TERMINAL 3 of the A/C single pressure SW --> TERMINAL 2 --> TERMINAL 2 (5S-FE), 1 (7A-FE) of the water temp. SW (For Radiator Fan) --> TERMINAL 1 (5S-FE) --> Ground, and the Fan Relay No.1 and the Fan Relay No.2 are turned ON.
At the same time that this current flows, current from the ECU-IG fuse flows to the Engine Main Relay (Coil Side) to Ground, causing the Engine Main Relay to turn ON. As a result. current from the ALT fuse flows to the CDS fuse and RDI fuse.

^ Low Speed Operation
When the Ignition SW is turned ON and the A/C is activated, current flows from the A/C magnetic clutch relay (Point Side) to the Fan Relay No.3 (Coil Side) --> Ground, causing the Fan Relay No.3 to turn ON. As a result, current from the CDS fuse flows to TERMINAL 2 of the A/C condenser Fan Motor --> TERMINAL 1 --> the Fan Relay No.2 (Point Side) the Fan Relay No.3 (Point Side) --> TERMINAL 2 of the Radiator Fan Motor --> TERMINAL 1 --> Ground, and each of the Fan Motor, with the result that the Fans are activated at low speed.
If the Engine Coolant Temperature is Approx. 90° C (194° F) or less, and the refrigerant pressure is Approx. 15.5 kg/cm2 (220 psi, 1520 kPa) or less. both the water temp. SW (For Radiator Fan) and the A/C dual pressure SW are closed, so that the Fan Relay No. 1 and the fan Relay No.2 are turned ON. As a result, each of the Fan Motor Operate at low speed.

^ High Speed Operation
When, during A/C operation, the refrigerant pressure becomes higher than ordinary level (Approx. 15.5 kg/cm2 (220 psi. 1520 kPa)), the A/C single pressure SW is turned OFF. As a result. the Fan Relay No.1 and the Fan Relay No.2 are turned OFF, and current flows from the RDI fuse to Fan Relay No.1 (Point Side) --> TERMINAL 2 of the Radiator Fan Motor --> TERMINAL 1 --> Ground, and current from the CDS fuse flows to TERMINAL 2 of the A/C condenser Fan Motor --> TERMINAL 1 --> the Fan Relay No.2 (Point Side) --> Ground, and to each of the Fan Motor in Parallel, thus causing the Fan Motor to operate at high speed.
Note that, because current flows in the same manner even if the Engine water temperature is Approx. 90°C (194° F) or higher, the Fan Motor still operates at high speed.