Weird Battery Gauge problem

[diesel_s]

Okay guys, here's the issue that has arisen. So i noticed yesterday out of the blue that when I came to a stop, my battery gauge dropped low, not to the point that the truck would pop up the red "check gauge" light and then cut but slightly above that. Then when i hit the gas, it would raise to near normal and stay there. So my immediate thought was that the battery was messing up and I was going to have to take advantage of my optima warranty and replace it but I tested it this morning with my amp o meter thingamajig and the terminals read 14 v like they should, so I decided to try it again later, I did it at random stops at random places all day and it read 14 v. Now that I know it isnt the battery and definitely not my alternator, i did some research and I heard about the BCM (body control module). My question is, what do you guys think? and what the hell is a BCM lol

 

[corkey]

did you have a lot of extra stuff running?
fan
stereo
lights

 

[diesel_s]

I tried it with the extras running, with the extras off and I even completely disconnected my sound system, radar, and indash nav and did it again. All three different ways at idle, I read 13 - 14 V and with the gas depressed i would be at 14 - 14.5 but my battery gauge in the car reads differently

 

[Jordan86]

I'm having similar issues as well. My battery gauge seems to drop lower when my headlights are on and when I use my turn signals. Would a belt tensioner going out cause these problems? My battery and alt checked and they were both good. Any help would be awesome, thanks guys

 

[diesel_s]

dude thats an excellent suggestion that I never once thought off...that would suck ass if i gotta change that damn tensioner though lol

 

[Jordan86]

Let me know if you figure anything out, I'll let you know something too if I figure anything out. I'm going to be messing with it today so hopefully I'll have some news and keep you posted, wish me luck