Grand Prix V6-191 3.1L (1989)
Heavy Duty Coolant Fan: Description and Operation
TURBO
The engine has two ECM controlled electric cooling fan(s). A primary cooling fan (#1) and a secondary fan (#2).
The primary cooling fan (#1) will be "ON" with any of the following criteria:
^
Coolant Temperature sensor signal indicating a temperature greater than 102~C (216~F)
^
A/C is requested.
^
A/C compressor, engine coolant temperature switch is "open" (pressure greater than 200 psi)
^
When ECM is in back-up mode.
^
Turbo models only, the primary cooling fan relay is wired so the fan can run with the key "OFF," and is controlled by the ECM. The ECM
will allow the fan to run approximately 2 to 480 seconds if MAP reaches calibrated setting.
The secondary cooling fan (#2) will be "ON" with any of the following criteria:
^
Coolant temperature sensor signal indicating a temperature greater than 104~C (219~F), and the A/C "OFF".
^
A/C is requested.
^
A/C compressor, engine coolant temperature switch is "open" (pressure greater than 200 psi).
NOTE: Both of the A/C intermediate pressure switches are in the same switch housing.
NON-TURBO
The engine can have one or two ECM controlled electric cooling fan(s). A secondary fan is added for heavy duty cooling for A/C.
The primary cooling fan (#1) will be "ON" with any of the following criteria:
^
Coolant Temperature sensor signal indicating a temperature greater than 106~C (223~F)
^
A/C is requested and vehicle speed less than 70 mph.
^
A/C intermidate pressure switch is "open" (pressure greater than 200 psi)
^
When ECM is in back-up mode, secondary fan (#2) will be "ON" with any of the following criteria:
^
Coolant temperature sensor signal indicating a temperature greater than 108~C (227~F), and the A/C "OFF".
^
A/C is requested and the vehicle speed less than 40 mph.
^
A/C pressure intermidate switch is "open" (pressure greater than 200 psi).
NOTE: Both of the A/C intermediate pressure switches are in the same switch housing.
