Mercedes ML270CDI engine coolant light and limp mode

[boystrat]

I have a 2004 ML 270, engine coolant light is now on and the car is in limp mode, i have been trolling the web and have found im not alone.....100amp battery fuse is good, however the 10 amp fuse located under the panel directly behind the engine bay fuse box, this is held down with 5 torx screws is blown, replaced fuse, 15 miles later fuse has blown again.....i have changed the radiator cooling fan assembly and yes.... fuse blew again.
can anybody point me in a good direction as all the info i can find conflicts and if i followed the advice id have a new motor!