Need Help -82 300D Dead

[sperry]

Thanks in advance.Last night I replaced the drivers side headlight.After replacement(pretty routine ) turned headlights on to check hi/lo beam & all worked well.Next I turned headlight switch off ,got in & turned ignition switch to start & noticed no glowplug light,radio or anything else came on.Removed key from ignition,tried again with no luck.Removed battery cables from battery,cleaned then reconnected.Battery voltage is @ 13vdc.Tried jumpering from anther vehicle & nothing changed.Would appreciate any suggestions on where to start diagnosing.

[jfreezn]

Originally Posted by sperry

Thanks in advance.Last night I replaced the drivers side headlight.After replacement(pretty routine ) turned headlights on to check hi/lo beam & all worked well.Next I turned headlight switch off ,got in & turned ignition switch to start & noticed no glowplug light,radio or anything else came on.Removed key from ignition,tried again with no luck.Removed battery cables from battery,cleaned then reconnected.Battery voltage is @ 13vdc.Tried jumpering from anther vehicle & nothing changed.Would appreciate any suggestions on where to start diagnosing.

Steve,

Do the headlights still work? If so, the problem could be a loose ingition switch. The switch is held to the back of the key switch with 3 small screws, which could have worked loose. On my 79 300SD, you have to pull the intrument panel to see these screws. Not sure if you can feel or probe the back of your switch from under the dash.

Power to the key switch is fed from a large ring connection on the starter solenoid. It is just convenient to pick up power from the positive cable at this point. The nut holding the cables (one big, one small) to the solenoid could be loose.

Not as likely, the big, usually uninsulated, ground cable running from the engine to the frame may have failed. Usually found running from the area of the starter mount over to the frame.

good luck,

Jim in Phoenix

[sperry]

Thanks Jim.Sorry I`ve not responded,just got bk in town.As a coincidence the next day after the initial no start, it started & ran perfectly for a few days.Yesterday it was dead again.No lights or signs of life except when i slammed the drivers side door the key in ignition buzzer would operate with ignition switch in on position,but nothing else would come to life.Any other suggestions as i will hopefully start troubleshooting this tonite.Wondering if their is a quick method of jumpering to get it started so i can reposition it in my garage?

[sperry]

Big Thanks to all who responded! The problem was the 8 inch long battery ground strap that connects to a bolt just in front of the battery. Loosened the bolt then tightened it securely and all is well.Hope this info helps someone else.