Hey. I want to convert my cig lighter to a USB port. Curious whether the power to it is allways on or only when the ignition is on. I’m not sure whether to get ones with lights or a voltmeter on as I don’t want to drain battery when not in use. thanks!

You can test it. Try the cig lighter with the ignition off. My USB port also lights up, but only with the ignition on. If it has a seperate positive connector for the lighting you should connect it to the same circuit. I actually connected my positive to the positive wire of my rear defroster, so I can flick the defroster switch and be 100% sure it doesn't dain the battery. My defroster doesn't do anything though 🙂 , might get too hot when you run it for too long

 

Thanks. I will give it a teat then. The switch idea is a good one. I might have to copy you haha. Cheers