Last week I went to drive my Audi a3 but had various engine lights and when the AA came out the diagnostic showed no faults, he unplugged the battery and replugged it in but no change. He suggested the instrument cluster was broken. I booked it into the garage today and when I went to drive it a week later the dash board was back to normal. Is this a regular thing that it can just fix or could it be a connection issue? This is the first time it’s happened and owned the car since 2016