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Radiator fan control


Start temperature

Specifies the temperature when fan will be activated, activates Radiator Fan 1 output.


Start temperature 2

Specifies the temperature when fan will be activated, activates Radiator Fan 2 output.

Note: See dual fan mode setting below.



Specifies the fan hysteresis. Uses to prevent unnecessary on/off. Normal value is 2 deg C.


Disable above speed

Disable FAN output above the specified vehicle speed (if a speedsensor is mounted and configured).


Run fan on ac

Specifies whether to run the FAN output when AC is active.


disable fan when engine off

Function to disable this output when engine is off, regardless of the temperature set for activation.


dual fan mode

One output at a time - Runs both fans separately depending on start temperatures. Only one output is active at the same time.

both outputs can be on simultaneously - Both fan outputs can be activate at the same time.






In the above example, Radiator Fan 1 will start at 86 deg C, at 90 deg C, Radiator Fan 2 output will ALSO be active.




post shutdown cooling (requires ECU power hold relay)


Post key cooldown

Enable or disable the power hold relay feature to drive the coolant fan. External relay must be wired for this functionality, see power hold relay wirings.


Note: Engine FAN output is an on/off output used in combination with relay.





Example: Single FAN output


1. An output assigned as Engine FAN which will activate the output at 86 deg C coolant temp (CLT), and stops the fan output at 84 deg C and will not run the output if AC gets activated.



Example: Two different fans wired to vehicle, low and high fan outputs.


1. The engine fan output wired to the low fan, which will start at 80 deg C with 4 deg C hysteresis.




2. Activate an USER output (where the high fan is wired) and make settings like the above which will start the second fan at 96 deg C and when engines cools down below 96 deg C it will continue to run the fan for 12 more seconds before shutting it off.



Example: automatic start of fan + button to force activation


In the above example, the fan output will be activated when cooltant temp (CLT) is over 80 deg C OR if the digital input 1 is activated, (this can of cource also be a MDash switch).