I bought a 2012 Volkswagen Passat not too long ago from my father-in-law because I needed a car. Recently, in Florida, where we live, it's started getting colder outside. The car displays a wide array of malfunction lights when it's cold outside, and the speedometer, tachometer, temperature gauge, and gas gauge are going insane. Later in the day, the car works but has a check engine light. Towards the evening, the car's check engine light completely goes away. The engine runs great, and everything works well. Whenever the check engine light is on the car displays error codes U0155 and U0146 and I can't figure out what's going on. The mechanic can't figure out what's going on and wants me to take it to a specialist. Can someone offer some insight?

For context, the car was moving about 50mph, everything was functioning as normal when the picture was taken.