Riviera V6-3.8L SC VIN 1 (1995)
Radiator Cooling Fan Motor: Description and Operation
The PCM and three relays are used to control the operation and speed of the engine cooling fans. When engine coolant temperature exceeds 212° F or
if A/C is requested, the PCM completes a ground path for the winding of the low speed fan relay. As part of the resultant series circuit, the cooling
fans share a single ground and battery feed and both fans run a low speed. The PCM operates the fans at high speed when engine coolant temperature
exceeds 226° F or A/C refrigerant pressure exceeds 200 psi and the A/C head pressure switch is closed. For high speed fans operation, the PCM
provides a ground for the low speed and both high speed relays. With all three relays energized, each cooling fan is supplied with its own ground and
battery feed, and the fans run at high speed.
