Daewoo FRS2031 - Mystery!

This side by side F/F, triple thermostat, has developed a very mysterious fault that so far has beaten all of the engineers that have looked at it.

Fridge side works perfectly. Compressor runs, fans run, temperature regulates etc etc.

Freezer side: If select 'super freeze' (which lasts for 150mins), fan runs and freezer rapidly reached temp of -26C. After 'super freeze' finished, temperature in freezer slowly gets warmer (-2C within 2 hours) before fan starts running again, which then switches off at around -8C, even though freezer is temp set to -25C. Problem here is that door only needs to be opened two or three times before food starts to defrost!

So far, engineers have replaced F sensor, D sensor, PCB Mainboard, dryer and cleaned and re-gassed - none of which has worked - and are now scratching their heads!

Anyone out there any ideas? Also, does anyone know what the 'default' setting should be for the FRS2031 or how to enter diagnostic mode? The engineer manual (thanks Nike123) gives two methods of entering self diagnostics. The first (Lock on, Hold Freezer Set, Press Refrig Set 5 times) actually enters forced defrost mode and the second (Lock on, Hold Refrig Set, Press Lock 3 times) does nothing. Have found, however, that Lock on, Hold Refrig Set, Press Super Refrig 10 times and Lock on, Hold Sleep, Press Freezer Set 5 times, both give loads of engineer setable parameters but engineer manual doesn't cover what they are or what they should be.

Any help would be much appreciated.

Thx fmb

HI fmb, there never was a "refrigeration" fault as the freezer is capeable of -26c. Selecting superfreeze just over-rides processor parameters to run freezer full on, the tricky part now is why the fridge/freezer fails to re-establish programmed settings. My first thought was processor failure but this now has included the interface between display pannel and processor. can't help with codes though, .. mike.

Thanks Mike - Front display panel seems to be behaving itself and physical connection between the two OK. One thing I'd never noticed before is the 'silent' icon appears illuminated all the time - can't remember whether this is normal or not.

For those who are reading this post, the usual turn it off, leave it off for 4 days, and turn it on - didn't work.

SO.. FMB, are you saying that the fridge side is o.k. when all this trouble is going on with the freezer? I wonder if this fridge has a liquid line solenoid valve for the freezer or there are two compressors? Any chance of a pic of the exposed back of this fridge?