Hello all

My thermo fan isn’t working and I believe it’s the sensor, I’ve ordered one and should have in a few weeks.

In the meantime, does anybody know what the oms reading cold and hot it should be for my existing sensor? Want to double check it by dropping it in boiling water to test existing one.

I have also rewired the bike with a motogadget 
M unit, and the relays are good.

Any help would be much appreciated.

Thanks

Go to the other kbike forum. http://www.motobrick.com/index.php?topic=11299.0
In that post, I included a link to an excel sheet with data and a graph of the response curve for the sensor.

If you bypass the sensor you can hook 12 volts directly to the fan and see if it turns. Does the fan turn freely when you turn it by hand. With the engine off, side panels off you can get your hand in and turn the fan.

On my 86 K100 I found that the insulation had burnt off the wires going to the plug on the fan. Surprise the fan still worked, but it was fairly stiff so I ended up taking the fan out and lubing it and repairing the wiring. Works fine now. So there are other issues that can affect the fans operation.

Thanks for the info!! Yes fan works! Looks like it is the sensor, will know for sure once it arrives.

To isolate the failure to either the temperature module or the sensor, ground pin "E" on the temperature module. If the fan comes on and the overheat indicator on the dash also comes on, then it's likely the sensor. If not, then it's likely the temperature module.