Doesn't "always run" only when needed:
Code:
The auxiliary or a/c condenser fan in mounted to the front of the radiator. The auxiliary fan for this vehicle is controlled by the ECM and does not use relays. The auxiliary fan request comes from the IHKA control module via the K-Bus. The fan speed request is based on the refrigerant pressure sensor input to the IHKA. Additional factors monitored by the ECM that influence fan operation are: Radiator outlet temperature sensor (exceeds the preset temperature), Vehicle speed, Battery voltage level. The auxiliary fan motor incorporates an output final stage that activates the fan motor at variable speeds. The output stage receives an output signal (pulse width modulated 10-100Hz) from the ECM, which activates the motor.
When it's hot out it might always run. When it's 75F it might never run. Like I mentioned above I had the AC running it was maybe 75F outside, I stopped the mechanical fan with some cardboard and within seconds the electric fan kicked on. When I let the mechanical fan free the electric fan stopped within seconds.