Stop in for a cup of coffee

I think the gauge i have in the fargo is a s/w. Sure beats the inaccurate factory gauge in my gmc. Good approximate info.
When my 2nd battery in the back came into contact with a piece of steel and shorted, and truck stalled, the gauge did indicate a problem. The smoke billowing out of the topper was the secondary indicator, forcing me to jump into action. Hindsight, shoulda let it burn...