The light that is supposed to light up when you turn the ignition to "on" has not been lighting for a while on my 2006 5.9. This is the little light that usually indicates the glow plugs working. It has been hot here in MN, but I thought this light was still supposed to come on in cold starts.

 

It wont come on when its hot out. 50 or 40 degreesthen mine starts coming on. The Cummins doesnt use glow plugs, it uses pre heater to warm up for "cold weather" starts.

 

he is right ^

 

Mine did that for awhile too, but then started working again. I thought it had something to do with the edge box but idk. All is fine now tho. Only happened for a few days.