I have a Buick lacrosse 2014. How can I keep the radio on without the ignition on?

Do you have a push button start? If so, just pushing to button to "Acc" (Accessory mode) should allow you to play the radio without turning the car on.

Yes, I do have a push button start, we did do that but then the ignition shuts off in about 5 minutes then the dome light comes on.

Retained Accessory Power (RAP) This vehicle has RAP. When in RAP the audio system can be played even after the ignition is turned off. See “Retained Accessory Power (RAP)” in the owner manual.

Let me know what you find out! Don't be afraid to check out the Owner's Manual (which is hopefully in your glovebox!)

Nope, 10 minutes. Am wanting to go to drive-in watch moive / listen to it through stereo speakers, with the engine turned off..? Just like cars with a keyed ignition. Plse help

Probably a little late, but I found this in the Owner's Manual. Sounds like Service Only Mode allows the radio to work. Haven't tried it yet, but the manual makes it sound like you need to push the button again to turn it off, instead of timing out after 5 minutes. "With the vehicle off, and the brake pedal not applied, pressing and holding the button for more than five seconds will place the vehicle in Service Only Mode. The instruments and audio systems will operate as they do in ON/RUN, but the vehicle will not be able to be driven. The engine will not start in Service Only Mode. Push the button again to turn the vehicle off."