Radiator and Condenser Fan Controls
Fan control system:
The cooling fan system is comprised of radiator fan, condenser fan (left, right), engine compartment fan, radiator fan
low relay, radiator fan high relay, condenser fan relay, engine room fan relay, radiator fan resistor, coolant temperature
sensor, A/C pressure switch, cooling fan control unit, climate control unit, and PGM-FI ECU.
The fan control unit controls the operation of the radiator fan and condenser fan.
It uses inputs from the coolant temperature sensor and A/C pressure switch (A and B) on the A/C system to determine
when the fans should run and at what speed.
Additionally, the temperature switch shuts down the A/C system if the coolant temperature exceeds 130°C (266°F).
If the pressure in the A/C system is higher than normal, pressure switch A closes and the fans will run at high speed only.
See the A/C section for description and specification of that funciton.
Fans operating condition: