Hello and welcome,My name is Steve and it will be my pleasure to assist you today.
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I would start by checking all fuses if you have not.
if fuses are okay, you can try unhooking the vehicle battery for one hour to reset all systems. wait 30min after turning the car off before unhooking the battery.
if the problem persists, then you are looking at component failure. the possible failed components would be the navigation computer, amplifier, ignition switch, remote receiver, general module.
unfortunately none of these components are intended for manual diagnosis, so the next step would be to have the vehicle scanned with a factory level diagnostic computer.
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Please let me know if you have further questions. Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you. Best wishes with your vehicle.