Diagnostic Aids
WARNING: This page is about a different car, the 2016 GMC Acadia, 2016 Chevrolet Traverse, and 2016 Buick Enclave. However, it is still accessible from the selected car via links, so may be relevant.
- The ECM has the capability of providing command to the fan relays even when a scan tool output control is being used. Always refer to the fan control command parameters on the scan tool to know which fans are being commanded ON by the ECM.
- The scan tool cooling fan output control operates as follows:
- Cooling Fan Relay 1 operates both fans at a low speed
- Cooling Fan Relays 2 and 3 operates one fan at a high speed
- Cooling Fan Relays 1, 2 and 3 operates both fans at a high speed