I made the mistake of riding my 1990 1000F doing a lot of stop and starts where i got it to the point of major overheating and steam everywhere.It got to the point where it melted the plastic Y union on the side and was leaking fluid pretty bad.And end result is that it killed the fan but i dont know where the malfunction is now.I replaced the entire thermo housing unit including the sensor and thermostat,the fan thermo switch on the radiator and have done all of the electrical tests to find out if any of the parts were bad.The thermostat and thermo housing switch were bad so thats why the replace but now all switches are replaced/tested and work fine.(The fan has always passed an electrical test)But still when i let it run and get it to temperature the fan does not come on SO what i was wondering is how can i bypass all of the possible problems and just hot wire the fan to the battery? Then use a toggle switch to turn it off/on. I saw that was used/mentioned in other posts but no explanation on how to hook that up.I will take it to a shop if i cant find the original problem but A)Id like to get her there on her own and B)Id like to be able to use her for awhile for some business that is pressing.Ideas?

 

You take the lead off of the sensor and ground it. see if the fan comes on. if it does then it is the sensor that is bad. or you can run the senor wire to a switch and the other to ground. Then the fan should work. Check fuses before doing anything also. Hope this helps

 

Yup +1

extend (add a piece of cable) to the cable from the fan switch up to one post on a toggle switch (located at a
site of your choosing) and the other post on the toggle switch to be wired to the
frame (ground it ! ) should then turn on an off at the flick of the the other wrist

 

Obvious question is obvious: check the fuse?