Originally Posted by
Castokrk
Hi Pizzaguy - so, I realized that the fan is not coming on at all hence it runs hot just sitting at idle. I replaced the fan and still no luck. 50 AMP fuse or do you still think it is the sensor? I think that the fuse is blown because I can not read the "50" on it like I can on the other one or on the 200 in the same box, but am not sure as I have never seen these mounted type fuses before.. thoughts???
Well, if you fan is not coming in, THAT is why the damn light is on. The ECU is not getting the response it wants from the Fan Control Module.
Check the 50 amp fuse, if it's OK, order a FCM. They are EASY to change, two bolts and the connector is a quick-connect thing - super easy. Search "2003 Mercedes SLK320 Fan Control Module".