I just bought a 1997 grand voyager 3.3. I bought it from a motorauction in UK and the battery was flat when I got.
After jump starting the car the airco turned out to be empty, so I thought that must be the reason for the flashing lights on the climate and rear wiper buttons. Filled up the airco, changed the battery, but still blinking lights.
They keep blinking for about half an hour and then they are fine. It looks like it needs a reset somewhere since the airco has been empty. I am surprised this issue is not in the present threads or at least I couldn't find it.