Intermittent auto gear shift issue
I have been using a 159 2.2 JTS Selespeed for a couple of months now. The odometer is at 62,000 km. I have been having some issues with the auto gear shifts, they intermittently shift from 1 to 3, and remain at 3 without shifting up or down. Or at times, it remains at 2. This issues started at 40,000km reading. It has happened 4 times in the past 20,000 kilometers. I have been advised to disconnect the battery terminal for a couple of minutes and connect it back. This works, but the issue comes back. Any ideas, suggestions or recommendation to permanently fix this would be most welcomed. Thank you very much. By the way, I noticed the "Check gearbox" display once.