I have a Euramobil 2003 motorhome 2.8JTD when driving up a hill the diesel light will come on when at top of hill and changing down gear van not on load the light will go out, in the manual it says its nothing to worry about if the light stays off, i have another problem now is when going up hill in 3rd the diesel light will come on then change down to 4th at top of hill enging no load then there is no power like going into limp mode, change gear to 3rd then you have power again, its very strange to diagnose, can anyone help please?