Q: Dash lights flashing on while driving

2013 Grand Jeep Cherokee Laredo, This car was recently purchased. Within ten days of purchasing it the issues began. The first time I was traveling on a highway still accelerating at around 52 mph, all the dash lights flashed on (everything the lights that flash on when first starting the car) and the car dinged at me like it does when I start it or do not have my seatbelt on. It happened quickly twice in succession. Three to four days later driving at night the dash lights and headlights flashed off for a second, very scary, I was on a back country road!! No sounds happened that time and the numerous dash lights did not flash on. Two mechanics told us that there were inactive error codes but they don't know what caused this to happen. They put 230 miles on the car and it didn't do it. I got it back and within 3 days it happened again with dash lights all coming on and car dinging. I would appreciate any ideas and some education on why error codes exist if they don't help?

My car has 52000 miles.
My car has an automatic transmission.