>>>>Last night the car cranked a little harder than normal and the light came back on but dimly, I drove home (20 miles) with headlights, radio and heater blowing and no battery light on but when I pulled in the driveway and put it in park the light came back and when I cut the headlights off the battery light glowed very brightly......

Stop right there - now exit the car while leaving it running!!

Step inside and enjoy a cup of coffee.... then check on the car periodically to see if the warning light eventually dims and then goes out.

After you have tried this experiment...... even idling your diesel for an hour or two or three (as might be necessary for crummy, stone-dead battery) return to this thread and tell us the results.

Another idea is to fiddle with the idle speed adjustment to see if diesel rpm has any effect on whether bright warning light goes dim...... If it dims at higher idle, then you might just have a loose or slippery fanbelt.

By all means, check the dash lights and guages at 20-30 minute intervals during your evening diesel watch...... and dont worry about an idling diesel depleting your battery with no electric components operating - diesels do not rely on electricity for operation.