Hello, don't forget the cigarette lighter only gets power when the ignition is on, or the engine is running. if you want to listen to the radio without the ignition on, there is a terminal on the ignition switch on 280's, "R", which is powered when the key is turned, but without the ignition on, so you won't risk leaving the radio on when you leave the car
Have a look on here, i understand this terminal is prewired to the ancillary fuses in the engine bay, i'm not sure if there is then an output wired from the fuse to the radio position, of if you need to wire from there yourself. Alternatively you could just wire directly from the R terminal on the ignition switch, with an inline fuse
https://www.sl113.org/wiki/Electrical/Radio#RadioInstall