chuckdee60

hi guys i recently purchased a 2003 clk 500 coupe,car drives very well.i recently was getting a low coolant error on dash but no check engine light.coolant level is where it should be.i used a cheap code reader and codes p0600 and p0410 came up.i also noticed coolant fan wasnt coming on and car was running around 100 celcius and the air was blowing hot. i checked the coolant fan plug(4 pin plug) and it has power coming from the prefuse block. i checked for visual broken wires etc and all looked ok. yesterday i started the car and it ran fine and fan was running and it had no low coolant error. drove it around for about an hour and all was ok. now this am the temp was approaching 100 celcius. is it possible the ecu is bad on the car? it has 88k on it just putting that out there. any help is apprecated thank you