Riviera V6-231 3.8L VIN C SFI (1989)
Radiator Cooling Fan Motor Relay: Description and Operation
A high and low speed fan relay are used on the standard system. An extra high speed fan relay is used for the optional (V08) fan. The ECM controls the
engine coolant fan relay under several operating conditions. If the coolant temperature sensor indicates high engine temperature, the ECM will energize
the relay to turn "ON" the fan. If the A/C is engaged, the ECM will turn the coolant fan on to cool the condenser as well as the radiator. Some fault codes
will cause the ECM to turn "ON" the fan. Above certain vehicle speeds, the ECM will de-energize the fan relay since at higher road speeds there is
ample air flow.