Manual fan switch diagram


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Does anyone have a diagram or tutorial how to install a manual fan switch? From what I understand you just run it off the battery >fuse> switch> fan power. It is for a track bike and currently my fan is kicking on pretty much right as I park the bike after a session. Would like to run it when I come off the track and after the bike is off.

Paging Fasteddy;)


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Looks like you can put positive voltage to the Fray/Yellow fan motor wire. Unless you use a heavy duty switch, you should also add a relay to the new circuit. I'm attaching a shot of the relevant part of the schematic.RC390 Fan fuse relay and motor.JPG


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I'd rather not put a positive power source to the grey/yellow stock wire (power source) for the fan. Two reasons.
- There would be a short circuit when the actual fan turns on at 96/97 degrees Celsius
- Just leave the stock circuit as is, as it is connected to the ECU
I'd rather remove the stock fan, install 2 fans beside each other, have one directly switched to the battery and the other to work as per the ECU/temp sensor.

Hope this helps.


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You could put a diode up stream of the power feed and manual switch for the fan inline with the power feed of the ecu. That should keep it from shorting. Hopefully a real electric engineer will chime in lol.