I have an F350 DIESEL 1999 which does not start . When turning the ignition key the lights dim on the dash but there is nothing more. I have disconnected the batteries, cleaned all the terminals and charged them but still nothing. I have also checked the connections to the started motor which are secure. Untill now the truck has always started without the slightest sign of a problem. Any suggestions.

ps; is there anywhere on the internet where I can look up a workshop manual or wiring diagram.

Many thanks , Peter.