Yes it is. When you turn the car off, even with no key inserted , you can listen to the radio for 20 min. I tried it but didn't wait to check on the 20 min allowance time. I think even when you just enter the car and without inserting your key, you can still able to listen to the radio

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X5 3.0i SUV
2005 -113000 miles
GM-A5S 690R Tranny