850 T-5R L5-2.3L Turbo VIN 58 B5234T5 (1995)
Radiator Cooling Fan Motor: Description and Operation
Engine Cooling Fan
PURPOSE
The ECM controls an electric engine cooling fan to maintain engine operating temperature. The ECM uses the following input signals to
determine fan speed operation:
- engine speed signal (from RPM sensor)
- vehicle speed signal (from speedometer)
- A/C temperature control setting
- A/C system pressure
LOCATION
Cooling fan - in front of radiator
Fan relay - On relay shelf, top of radiator
OPERATION
The fan is a two-speed unit. Low speed is used to control normal operating conditions. High speed is used only if engine over-heating is
immanent or if A/C system pressure is too high.
The fan is started when engine coolant temperature exceeds the normal operating limit of 216° F (102° C) or if ECM internal temperature exceeds
176° F (80° C).
With A/C the fan operates when:
- the A/C is "ON" and vehicle speed low
- A/C system pressure is high
When engine is stopped the fan operates:
- for 6 minutes if the engine was running at high load and high temperature immediately before being switched off.
- for 3 minutes if the fan was running at full speed when the engine stopped
