I bought this for my fiancee and the warning light keeps coming on if it is sitting still for a few minutes. The fan does not come on and I made sure the coolant was topped off. What gives?

 

Is it brand new?

If it doesn't have any miles on it, maybe it is still breaking in? When I put on my 351 kit, mine did the same thing. After the first couple of rides, it went away.

Maybe it is just a faulty sensor? I assume you have a 09 or newer, what does the temp gauge read?

 

No, it's actually a 07' that I bought with 550 miles on it. So no temp gauge, just a warning light. I don't want to overheat the practically brand new engine. Not sure what to do here. Do I need to check the fan switch? I've read that a lot of peoples fans hardly ever come on. Everything is stock on the bike.

Side note, I accidentally twisted the warning switch wire and it split so i'm gonna try to solder it back together to the 1/4" protruding from the switch. Hopefully I can avoid an $80 mistake. *fingerscrossed*

 

The fan on this bike rarely turns on, unless your going slow with over 1/2 throttle.

Take the rad cap off after it has been warmed up, don't burn your hand or face with steam.
1. Is the radiator water boiling? If yes, then something is wrong. Sensors probably, fan or pump.
1aoes water appear to be flowing? Then pump is working.
1b. Test fan:
Test the rad fan. With the switch on (can be done without warmup), ground the black wire coming out of the radiator fan relay. Fan should start. If not, investigate fan relay & fan (test fan alone by jumpering black/blue and blue wires (leave the black wire alone) together at fan relay).
1c. Replace the fan temp sensor.
2. Rad water is not boiling, use a meat thermometer or stick your finger in there is it not real hot and the warning light is on? Replace warning light sensor.

 

The light comes on if you let it sit in neutral for a couple minutes. Thanks for the advice! I will check it out like that after work.

 

You can remove the light and fan switchs and check it in heated oil. Use a good thermometer in the oil and a multimeter to check resistance. Instructions in the manual. Be sure to submerge it properly in the oil bath (per instructions). Check the light switch. Check the fan circuit. In my experience, the fan came on well before the light (that is before switching to Engine Ice with the 351 kit, but that's another issue I'm still trying to figure out).

Prior to 351 kit, I had the fan come on a number of times. Even going down hill very slow with little to no throttle and slow climbs on hot days. Idling too long (more than 2 minutes for sure).

 

never had the fan come on yet even in 90f temps
but street riding only maybe it just kept it cool enough

my drz400 would come on once in a while on the street hot days


maybe it has an air bubble in the system?

 

Ok, so I just finished playing around with it. I topped off the reserve with maxima coolant/antifreeze. Then I soldered the warning switch back together, took off the radiator cap and let the bike idle for about 5 minutes in the garage. About sixty seconds after I saw little bubbles in the coolant and it was steaming the warning light came on. After the warning light was on for about 45 seconds I put the radiator cap back on and the fan immediately turned on for about 15 seconds and then turned off. So I took the radiator cap back off and put it back on and the fan immediately turned back on for another 15 seconds. So am I right in assuming this is a problem with the fan switch? If so, I will go ahead and buy the fan switch and a warning light switch to be safe.

 

OK, you got it figured out... So your fan is controlled by the position of the radiator cap. Now you just need to find a way to get a handle extension for it and....

Seriously, the fan is controlled by the switch and a control relay. See my previous comments.

Oh yea, don't forget to top of the radiator in the maxima too!

 

So what is it that I need? All of my other bikes are air cooled and I just got this klx and a klr650 within the last two months. I am learning about liquid cooled engines as I go along. So I assume that I need to get a new fan switch(#27010) and while i'm at it I might as well get a warning switch(#27010A) but do I also need to get the relay assy(#27002)? And do I really need to top off the radiator? I thought that was what the reserve tank was for. Again, sorry for my ignorance as I have never dealt with radiators before.