I have a 2018 Tahoe and my backup camera will not shut off. My reverse lights will also remain on while the truck is in drive. The normal display screen comes on when the key is turned to accessory mode but once the ignition is turned the backup camera comes on. I took it to the dealer last week and they charged me a $150 diagnostic fee and called me the next day and said they needed more time to figure the problem out and would be an added $150 per hour until they can figure it out. I decided to decline the service especially not knowing how much it was going to cost just in diagnostic fees. Anyone know what the issue could be? Thanks