Alero L4-144 2.4L DOHC VIN T SFI (2000)
and will occur if any of the following combinations of conditions exist when the ignition is turned off:
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The Engine Coolant Temperature (ECT) is more than 100°C (212°F) and the Intake Air Temperature (IAT) is more than 80°C (176°F).
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The ECT is more than 112°C (234°F) and the IAT is more than 70°C (158°F).
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The ECT is more than 116°C (241°F).
The PCM and the cooling fan will remain on until these combinations of conditions no longer exist, up to a maximum of 7 minutes.
If the cooling fan is off when the PCM powers down, the fan will remain off regardless of temperature until the ignition is turned on again.
DIAGNOSTIC AIDS
If the owner complained of an overheating problem, determine if the complaint was due to an actual boil over, or the warning indicator lamp. If the
engine is actually overheating, but the cooling fan is not coming on, the ECT sensor has probably shifted out of calibration and should be replaced.
If the engine is overheating and the cooling fans are on, the cooling system should be inspected. Refer to Engine Overheating in Engine Cooling. See:
The Body Function Controller (BFC) will command the PCM to enable the low speed fans on at 106°C (223°F) and off at 103°C (217°F) and the
high speed fans on at 111°C (232°F) and off at 108°C (226°F).
TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
6. Ambient temperature must be above 9°C (48°F) before the PCM will enable the cooling fans due to A/C request. The PCM will enable the cooling
fans if A/C refrigerant pressure increases, regardless of the ambient temperature.
78. The replacement PCM must be programmed and the Crankshaft Position System Variation Learn procedure must be performed.
