noacluck Posted April 13, 2017 I have a 2008 KTM EXC that had an aftermarket radiator fan installed by the previous owner and worked fine up until some heavy trail riding a while back. Im pretty bad with electrical stuff and havnt even owned a bike with an electric start until now. Ive heard having a fan on these is pretty much a necessity so Im trying to get it working. Ive heard I can test if the fan will work by touching two wires together but I dont know which ones. Also how can I check to see if its a fuse or something else? Thanks! Share this post Link to post Share on other sites
SnowMule My Rides (4) Posted April 13, 2017 A tool you'll find handy is a multimeter. Doesn't have to be a fancy one, just something that'll do resistance and voltage (they usually do current measurements too). The fan is connected to power through a thermostat switch. Temp goes up above a certain level, thermostat switch closes, connecting fan to power. Temp falls, switch opens, fan stops. The two wires "shorting together" is the two on the thermostat switch - closing the fan to power. If the fan runs, you've found the problem - the thermostat. Replace that. If the fan still doesn't run, it's probably not the thermostat. Look in the owners manual for wiring diagrams, and follow those wires measuring voltage along the way till you find where you don't have power anymore. 1 Share this post Link to post Share on other sites
sirthumpalot Posted April 13, 2017 Depending on how your fan is wired; if you can get to the fan wires directly, or to the plug that goes to the fan directly, then connect the wires to 12v and see if the fan runs. If yes, then the fan is OK. If no, then the fan is bad. Share this post Link to post Share on other sites
noacluck Posted April 13, 2017 So for better reference, here is what Im working with. I know this should be very simple but Im not sure which one of these wires is the switch your referring to. And where do I get 12v? Is that just the battery on my bike? Share this post Link to post Share on other sites
UH1H Posted April 13, 2017 Easiest thing is to check the inline fuse.....mine quit working and the fuse was bad. Share this post Link to post Share on other sites