Haltech F9A - Manual (Page 92)

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5.4 Electric Thermatic Fan Control (TF)
This function can be used to switch on a thermofan when the engine temperature exceeds a
certain value. The fan will stay on until the engine temperature drops below a second value.
NB: The electric fan cannot be driven directly by the ECU. A relay must be used to switch the
high currents drawn by the fan.
To use this function, you must have the following:
- the F9A secondary harness incorporating the Auxiliary I/O connector;
- an electric thermofan, fused and relay switched;
- F9 programming software and cable.
Install the wiring for the thermofan to one of the Auxiliary outputs as described in figure
5.4-1. Be sure that the relay contacts are rated higher than the current drawn by the thermofan.
Run the F9 programming software and go to the Options page. Select the Thermofan function
on the appropriate output and set the two temperatures as required.
Switch On Temperature: The temperature the engine coolant must exceed to switch the fan
on.
Switch Off Temperature: The temperature the engine coolant must drop below before the
fan will be switched off. This parameter should be at least 5° lower than the Switch On
temperature to prevent the fan from switching in and out repeatedly.
Figure 5.4-1: Example circuit for thermofan control.