Adding a manual fan switch to your SVO

The stock engine fan controller does not turn the fan on until around 226F.  This is too late/hot in my opinion, so here is an easy way to add a manual switch to operate the fan.
by-pass front
The fan controller is located under the drivers side of the dash, below the headlight switch.
The controller is easily removed from under the dash to get the connector removed from the controller.

Splice a wire to pin 1 on the fan controller to a switch and the other end of the switch to a chassis ground. 

If you are running the L series computer, you can also connect EEC pin 55 to pin 1 on the fan controller and the EEC computer will turn on the fan at 220F

by-pass valve with bracket removed
There is the controller held by 2 screws.

fan-scm.jpg (30313 bytes)
The schematic taken from the Ford manual, shows that wire 8 could be O-BK or GY-Y.
fan-ctrl.jpg (163674 bytes)
Here is the fan controller circuit.   Click on the image to get the full size image.
Good luck!  I am not responsible for any problems associated with this modification.  This is only showing what I did to manually operate the fan.


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