Electrolux AEG Side by Side refrigerator too cold

Hi there, I am a domestic appliance engineer and have applied for access to the trade forums but require some help in the meantime. Fridge Model is S85628SK1 PNC 92846505405.

Original customer complaint was that the appliance was tripping their mains RCD, on investigation found this to be a leaky solenoid at the rear of the appliance that had leaked into the electrical harness feeding the fridge compartment.

Got the unit running again and stable but unfortunately the fridge compartment now runs at about -5 deg C with the digital display showing +36/37 deg C – obviously the unit is running constantly to try and achieve the setpoint temperature of +8 deg C. I checked and as a precaution replaced the NTC probe but it wasn’t giving a bad reading. Checked the resistance all the way back to the connector on the main PCB in the base of the appliance and all the wiring / connections are good. My question is whether it is likely to be the display / control panel on the door or the main PCB in the base that is causing the problem. I notice the display has some dead led segments and the touch activation is a bit intermittent. They are not cheap board so don’t want to spend a lot of the customers money unnecesarilly.

All help greatly appreciated. Apologies if its in the wrong section. Kind regards – Dave