coming out of the mountains last night. I noticed my voltage guage was running on the low side. using my idle controller I checked my output, 12 volts. A little later the battery light came on, but the truck is running ok. Headlights work, every thing works.
What do ya think, altenator, or could my glow plug relay be stuck on.
I had a code trip on the way out of the mountains but it was a " fuel pressure to low or to high " code which I tripped going around a curve

old truck drifts pretty good

So I cleared that code like normal and then it came up with p1111 code " system passed "
Any ideas?