Symptom:
Volt meter fluctuating and lights dimming after startup on cold morning?

This is Normal

Good info for new diesel owners on cold weather operation.
Cold Weather Diesel Opearation

Instead of using Glow Plugs like the Fords & Chevys, the Cummins uses 2 grid heaters in the intake tract to preheat the incoming air, each pulling 95 amps for a total of 190 amps! At 12 volts, that's nearly 2300 watts, one whopping load on the battery!
This will cycle on-off until the computer turns off the heaters at a preset temperature, or you exceed 25 mph.
Check your owner's manual for more info.

Ed
Moderator
3rd Gen Forums

(thanks to Tom Hybiske for the updated info)

 

Thanks for the info. I wondered bout that.