I have an '03 600 twin and the overheat light is coming on but I don't think the machine is overheating. It is not on when I initially start the machine, but once it gets to temp. the overheat light comes on and continues to blink. The machine is full of anti-freeze, the overflow is not spilling over or expanding like it would if it was overheating, the radiator has some debris but not too bad, the fan does come on and after it runs for a while it shuts off (normal operation), the whole time the overheat icon still keeps flashing. The machine does not smell or seem to be too hot and it happened this weekend bird hunting in Northern MN where the temp was 30 degrees and it snowed. I even took the radiator front screen off and ran the machine at 30mph to get additional airflow to the radiator. The icon still flashed even after the fan shut off. Is there any particular issue that anyone has had?? When I start it from a completely cold start the icon is not flashing.

 

Do you know if your coolant is flowing from the engine to the rad and from the rad to the engine?...Will it boil over from the overflow if you let it idle for a long time?
.....Caper............

 

I guess I'm assuming there is flow. The ATV does not seem to be running to hot. I did some digging and i'm wondering if the ECM controls the "idiot" light. Basically at this point i'm assuming there is some sort of malfunction because if the bike was actually running hot the fan would not shut off. everything seems normal but I do not know what triggers the temp. light The only sensor I'm aware of is the one that controls the fan and that does not control the temp. light.

 

There should be a sensor on the radator that controls the fan and there should be a sensor on the left side of the water jacket (when sitting on the machine) that is for the warning light. Not sure if this sensor is hooked into the ECM to tell the pod to kick on the warning? Maybe an ECM issue??Maybe the sensor is out of range???? Not sure on what they cost. Another thing you could do is hit the engine with a non contact temp gun when it says it is overheating to verify that it truely is not.

 

I called the dealer and the '03 does not have an ECM??They did tell me where the temp. sending unit is and I will check on that tonight. It is located on the right side of the motor, and has a single wire connected to it. According to them it only controls the idiot light and nothing Dealer cost for the part is $36.

 

In the real world we check overheats with infrared gun easy to do and very effective.

 

I already know know it's not overheating. I just couldn't find where the temp sensor was to inspect it for damage or failure. It was kind of hard in my "fantasy" world of being 230 miles from home and 10 miles deep in the woods to check the temp with my infrared gun....(LOL)

 

It should be on your left side of the block when sitting on the machine if I recall right.

 

Thanks for the help I got in touch with the dealer and they showed me which schematic to look at. Now I just need to get all the dirt, mud, and debris cleaned off so I can get at it..

 

that dirt and mud could be your cause also..... giving you a hot spot