Engine Cooling Fan Description - Electric

Primary Cooling Fan

The cooling fan switches (7 and 6) and the A/C compressor relay (instead of the ECM) control the relays which power the primary fan (5) and two secondary fans. The primary fan is a "puller" type; the secondary fans are "pusher" type.





Engine Cooling Fan Operation Parameters

The following table explains the temperatures at which the engine cooling fans are energized or de-energized:
The secondary fans are energized in a series (half speed) during A/C operation. This could be stepped up to full speed, or the primary fan could be energized as well, depending on the coolant temperature.