Whirlpool Built-in Fridge/Freezer ART 489 – thermostat problem

Hey,

We’ve got build-in Whirlpool ART 489 fridge (with freezer) and on the display for fridge temperature it shows E (with acoustic signal). According to the manual it means a problem with thermostat. However several times it stopped showing E for a longer period when I disconnected the display/control panel, moved the wires and later connected it back. It looks to me like a connection problem or maybe something with the board (some of the buttons don’t react on every push etc).

Any advice how to continue and isolate the problem to find the cause? The local service said they don’t do “digital” fridges and calling a service from a distant city can be pricey. Or maybe a service manual?

Thanks a lot!

Jan