On ebay you can buy a USB charger that plugs into your cigg lighter (no one smokes, right?).

Not only is it a charger, but it shows battery voltage. These cars don't have a voltage gauge and this is a great way to keep an eye on your alternator and battery!
They are like $5-$6 bucks! The one I got looks almost stock.

 

Personally I dont trust nothing cheap electronic on ebay. I had a buddy with an ford f350, had something similar plugged in and it burned his whole dash. If they made something of quality that would be worth considering. But to buy something for 5 bucks, its internals surely are the cheapest quality and for something electrical, that dangerous to leave plugged in all the time.

 

You could get something like this but you will need an app to read voltage.
Also doubles as a usb charger and a car finder.

 

I agree, but I did research and never read any complaints about these newer chargers burning up, not saying they don't however, If it can read voltage and current it is likely more care wen't into the device.

Also, our power port is shut off when the car isn't running, not a perfect solution but at least you will smell something first!

 

It's pretty common knowledge that those things are very inaccurate when it comes to voltage readings. I wouldn't trust one.

 

Mine matches an accurate multimeter. I have second thoughts now about this. Maybe I'll just keep it and plug it in occasionally to see battery voltage.I would even pay $25 if I knew it had no issues with overheating, but I don't see any that match what I have from a brand name.