Diagnostic Aids
WARNING: This page is about a different car, the 2017 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.
- The cooling fan will not operate when the scan tool Cooling Fan Motor Command parameter displays less than 4%. This is a normal condition.
- A delay or ramp up of approximately 12 seconds may occur before the cooling fan activates or changes speed when being commanded with a scan tool.
- The cooling fan Control Function operates as described below when the ignition is ON, and engine is OFF:
- Command State 1 operates the cooling fan at approximately 18-21%
- Command State 2 operates the cooling fan at approximately 54%
- Command State 3 operates the cooling fan at approximately 67%
- Command State 4 operates the cooling fan at approximately 85%
- Command State 5 operates the cooling fan at approximately 90%
- During normal operating conditions the ECM may initially activate the cooling fan at 4 or 5% and then increase to the percentages indicated above, as needed, to satisfy powertrain cooling requirements. Generally, the ECM will operate the cooling fan at the specified percentages but, may scale the percentages either higher or lower in response to generator demand.
- When operating the cooling fan with a scan tool, the Commanded States 1-5 should be exercised in order, from OFF to High or High to OFF. The cooling fan control module may disable the cooling fan if a Commanded State is skipped.