With Air Conditioning

OPERATION
Voltage is present at the cooling fan power relay contacts at all times through the cooling fan fuse link cartridge. The cooling fan power relay coil is grounded through the starter assembly.

With the ignition switch in "START" or "RUN", voltage is present at the coils of the cooling fan power relay, the cooling fan lo speed relay, and the cooling fan high speed relay.

With the starter cranking, voltage is present at both terminals of the cooling fan power relay coil; the contacts do not close and the cooling fans are not powered. With the starter not cranking, the cooling fan power relay coil is energized and the contacts close. Voltage is applied to the cooling fan lo speed relay and the cooling fan hi speed relay.

With engine coolant temperature below 220 degrees F, the Powertrain Control Module (PCM) immediately grounds pin 35 and the cooling fan lo speed relay coil. The relay energizes and the contacts open; the electric cooling fan does not run.

If engine coolant temperature reaches 220 degrees F, the PCM ungrounds pin 35 and the cooling fan lo speed relay coil. The relay deenergizes and the contacts close. Current flows through the cooling fan fuse link cartridge, the cooling fan power relay, the cooling fan hi speed relay (deenergized), the cooling fan lo speed relay (deenergized), and the electric cooling fan low speed winding to ground; the electric cooling fan runs at low speed.

If coolant temperature drops to below 212 degrees F. the PCM again grounds pin 35 and energizes the cooling fan lo speed relay; the electric cooling fan stops running.

If coolant temperature continues to rise until it reaches 230 degrees F, the PCM grounds pin 31 and the cooling fan hi speed relay coil. The coil energizes and the contacts close. Current flows through the cooling fan fuse link cartridge, the cooling fan relay, the cooling fan hi speed relay, and the electric cooling fan high speed winding to ground; the fan runs at high speed.