Two Speed Fan (A/T)

Voltage is present at the contacts of the Cooling Fan Hi Speed Relay at all times through the COOLING FAN Fuse Link Cartridge. With the Ignition Switch in START or RUN, voltage is present at the coils of the Cooling Fan Relay and the Cooling Fan Hi Speed Relay through the ENGINE Fuse. With the Cooling Fan Hi Speed Relay deenergized, voltage is also present at the contact of the Cooling Fan Relay.

If engine coolant temperature reaches 207 degrees F, the Coolant Temperature Switch (Fan) closes, grounding the Cooling Fan Relay coil. The Relay contacts close and power flows though the COOLING FAN Fuse Link Cartridge, the Cooling Fan Hi Speed Relay (deenergized), the Cooling Fan Relay and the low speed winding of the Electric Cooling Fan to ground. The Fan runs at low speed. The Fan will run at low speed until: a) the Cooling Fan Relay coil is no longer grounded and the Fan shuts off, or b) engine coolant temperature reaches 221 degrees F and the Coolant Temperature Switch (Radiator) contacts close. If the Coolant Temperature Switch (Radiator) contacts close, the coil of the Cooling Fan Hi Speed Relay is grounded, energizing the Relay and switching current flow from the Cooling Fan Relay Contacts to the high speed winding of the Electric Cooling Fan; the Fan runs at high speed.

When the Electric Cooling Fan is operating, a "fan on" input is provided to the EGI Control Module.

On vehicles equipped with air conditioning, the Cooling Fan Relay coil is grounded whenever the air conditioning system is activated, and the Electric Cooling Fan runs continuously at low speed.