System Outline

FAN MOTOR OPERATION (W/ AIR CONDITIONING SYSTEM)
With the ignition SW turned ON, the current through the HEATER fuse flows to the FAN NO. 1 relay (Coil side), FAN NO. 2 relay (Coil side) and FAN NO. 3 relay (Coil side). Furthermore, the current through the FAN NO. 1 relay (Coil side) or the FAN NO. 2 relay (Coil side) flows to TERMINAL 3 of the A/C single pressure SW to TERMINAL 2 to TERMINAL 2 of the water temp. SW no. 1 to TERMINAL 1 to GROUND, causing the FAN NO. 1 relay to turn OFF and the FAN NO. 2 relay to turn ON.

1. LOW SPEED OPERATION
Only when the A/C system is activated or the water temp. SW no. 2 is turned ON, the A/C condenser fan motor and the radiator fan motor rotates at low speed.

When the A/C system is activated, the current from HEATER fuse flows to the FAN NO. 3 relay (Coil side) to TERMINAL 13 of the A/C amplifier, causing the FAN NO. 3 relay to turn ON. As a result, the current through the CDS fuse flows to TERMINAL 2 of the A/C condenser fan motor to TERMINAL 1 to TERMINAL 3 of the FAN NO. 2 relay to TERMINAL 5 to TERMINAL 3 of the FAN NO. 3 relay to TERMINAL 5 to TERMINAL 2 of the radiator fan motor to TERMINAL 1 to GROUND. As the current flows in series to the motors, the motors rotate at low speed.

When the water temp. SW no. 2 is turned ON, the current from HEATER fuse flows to the FAN NO. 3 relay (Coil side) to TERMINAL 1 of the water temp. SW no. 2 to GROUND, causing the FAN NO. 3 relay to turn ON. As a result, the current through the CDS fuse flows the same route as above, rotating the motors at low speed.

2. HIGH SPEED OPERATION
Only when the A/C single pressure SW is turned OFF or the water temp. SW no. 1 is turned OFF, the A/C condenser fan motor and the radiator fan motor rotate at high speed.

When the A/C single pressure SW is turned OFF, the current from the RDI fuse flows to the FAN NO. 1 relay (Point side) to TERMINAL 2 of the radiator fan motor to TERMINAL 1 to GROUND. At the same time, the current from the CDS fuse flows to TERMINAL 2 of the A/C condenser fan motor to TERMINAL 1 to TERMINAL 3 of the FAN NO.2 relay to TERMINAL 4 to GROUND.

As the current flows in parallel to the motors, the motors rotate at high speed.

FAN MOTOR OPERATION (W/O AIR CONDITIONING SYSTEM)
With the ignition SW turned ON, the current through the HEATER fuse flows to the FAN NO. 1 relay (Coil side), FAN NO. 2 relay (Coil side) and FAN NO. 3 relay (Coil side). Furthermore, the current through the FAN NO. 1 relay (Coil side) or the FAN NO. 2 relay (Coil side) flows to TERMINAL 2 of the water temp. SW no. 1 to TERMINAL 1 to GROUND, causing the FAN NO. 1 relay to turn OFF and the FAN NO. 2 relay to turn ON.

1. LOW SPEED OPERATION
Only when the A/C system is activated or the water temp. SW no. 2 is turned ON, the A/C condenser fan motor and the radiator fan motor rotates at low speed.

When the water temp. SW no. 2 is turned ON, the current from HEATER fuse flows to the FAN NO. 3 relay (Coil side) to TERMINAL 1 of the water temp. SW no. 2 to GROUND, causing the FAN NO. 3 relay to turn ON. As a result, the current through the CDS fuse flows through the same route as above, rotating the motors at low speed.

2. HIGH SPEED OPERATION
Only when the water temp. SW no. 1 is turned OFF, the A/C condenser fan motor and the radiator fan motor rotate at high speed.

When the water temp. SW no. 1, the current from the RDI fuse flows to the FAN NO. 1 relay (Point side) to TERMINAL 2 of the radiator fan motor to TERMINAL 1 to GROUND. At the same time, the current from the CDS fuse flows to TERMINAL 2 of the A/C condenser fan motor to TERMINAL 1 to TERMINAL 3 of the FAN NO. 2 relay to TERMINAL 4 to GROUND.

As the current flows in parallel to the motors, the motors rotate at high speed.