1984 300d. Ok, checked glow plugs they seem good. Fuse in relay good. Power good to relay box. No power to the 5 pins in relay box when key is turned. When engine turns over get power to the 5 pins in relay. Car starts hard but runs fine, but its been warm here , the glow plug light no longer lights. Any ideas? Don't want to get a relay if I don't have to. Thanx Jimmy