With the glow plug relay box; you mean the one under the dash or the little box on the firewall?

I have to replace the one on the firewall and will look at all the conections and clean them. Do I use some fine sandpaper?

Thanks

__________________
1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).