I have a USB micro charging adapter for my smartphone for my car. It is basically a cigar lighter plug that turns into a USB micro plug. When I don’t have my phone connected, and as such don’t want the adapter to draw any current, is it still safe to keep the adapter plugged in?
I’m wondering because most other AC adapters (i.e. those not for the car) usually keep drawing some current, even if no device is connected. Is that also the case for those car adapters? Should I rather unplug it whenever I don’t need it?