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Electric Cooling Fan Control

NOTE: For electric cooling fan circuit testing, see ELECTRIC COOLING FANS article in AIR CONDITIONING & HEATING. See appropriate wiring diagram in WIRING DIAGRAMS article for terminal and wire color identification.

All FWD and some RWD vehicles use an electric cooling fan. The electric cooling fan is used for radiator and A/C condenser cooling. Cooling fan operates when A/C is on and when engine coolant temperature exceeds a specific value. One or more cooling fan relays may be used. Some RWD trucks, vans and motorhomes are equipped with an auxiliary electric cooling fan.