Cooling fan actuation issues......
 

Hi all. Newb here. I just got my 98 Superhawk a little over two months ago. Not my first twin cuz I've fallen in love with the damn things but it IS my first non-EFI bike so I'm trying to quickly acclimate myself to the "subtle" differences. First off, let me apologize if my question has already been answered in a previous thread. I did do some searching in historical threads but didn't see what I was looking for and the slowass puter at work coupled with my impatience has now yielded the following......

My issue is that my cooling fan won't kick on with the engine running. Per what little information I've gathered, I know that the fans should begin operating when my temp gauge gets in the 3/4 range and continue doing so until the temp falls back below said range. And they do. But not unless I cycle the ignition key off (killing the engine) and cycle it back to start/run.

Verified operation of the ground circuit BEFORE the coolant temp sensor by simply jumpering the connector going to the sensor to the negative post of the battery. While I realize that still leaves some question as to the operation of the temp sensor (as it provides the ground for the fan), I'm more concerned with the power aspect of the circuit. I've verified power at the fan during idle (not working) and operating (working) states with the key in the start/run postion and the engine off. As soon as I start the engine, I lose power to the fan assembly. Turn off the engine and the test light illuminates once again.

Assuming I'm interpreting the jenky ass wiring diagram I have for the circuit, the fan should be hot at all times, if not with the key in the run/start position regardless of the running state of the engine.

Just curious if anyone has come upon and solved this problem as I'd like to actually fix it as opposed to Polish engineering a manual switch (and I can say that as I am of Polish heritage ;-)) so I don't overheat my poor engine.

Thanks all!!

So, you're getting power to the fan at all times except when the motor is running? Maybe the switch isn't grounded very well- another way to make sure the circuit is working is to take the wire connected to the fan switch and touch it to the radiator (b/c this is where the fan switch is grounded). If the circuit is complete, the fan will turn on. Your assessment that it does work when the key is on but motor isn't makes me think that this won't solve anything, but it's good to double check.

Okay. I must've had a poor conncection @ ground the whole time I was testing the circuit originally. Just did the "connector to radiator" test, fan operates, did it again with the engine running, fan operates. Checked for power @ connector with engine running, suddenly I've got power. Huzzah! Now to go ride this pig into the ground so as to test real-time fan operation.

Thanks so much!!

My fan comes on at about the half way on the temp guage. (just for reference) and I also installed a switch to turn it on when I deem fit. this way if the auto switch dies I can still get the fan to come on. I ride alot of city miles in 90* so it was needed. I also installed a ZX-7 oil cooler which help a ton too.