Could be the strip fuse inside the relay. Maybe a bad GP too. Not sure how different it is from the W123 diesels. Check the easy solutions first before ordering a new one.MBeige: thanks for the reply. I was sceptical about the bulb, given the car only has 57K on it. I almost hesitate (from fear) to ask where the glowplug relay is? I hope it isn't deep in the bowels of the dash, but maybe somewhere in the engine compartment where I can get to it easily??? Do you, by chance, have a picture o description of its location? Thanks again.