Very common problem on that fridge and a easy fix: Replace the two big capacitors on the right side of the control PCB 1uF = 0,68uF 250V They lost their capacity causing bad uC supply and this strange LED blinking. Be aware that this blinking can be intermittent and the fridge appears to return to operation. But the uC suffer a lot of internal resets causing intermittent operation stops, low temperature and more not easy recognizable or strange mal functions. So, if You face that blinking normally the capacitors are gone. Some strange and intermittent behaviors of the fridge are also back routed to this PCB - Capacitor malfunction. So enjoy this 30min fix. The capacitors should not exceed US$2 in Your local electronic shop. If You don't want to spend the US$2 You can find the capacitors as a lucky guy in a old PC power supply.
For other more complex problems be aware that the controller board has a very nice and helpful self test option. You go in this mode holding the temperature select button of the refrigerator (not the freezer button) then switch the fridge on and stay on holding the temp button for more 10s. The self test sequence starts in the moment when You release the temp button.
LED 1: Checking sensors (Blinking=OK - Continues=NOK, something wrong)
LED 2: The Flap opens and close two times (Alarm LED shows the open and close position, so the led must go ON and OFF two times in accordance of the detected flap position from the internal reed contact. (So, no action on the Alarm LED no movement on the Flap or a defect Reed contact)
LED 3: Fan goes ON and OFF
LED 4: Drain Heater goes ON and OFF
LED 5: De- Dicer Heater goes ON and OFF
LED 6: Compressor goes ON and OFF
LED 7: End of test sequence - Initializing procedure of normal operation.
Every step takes 30s and the whole sequence take tree and a half minute. Be aware that the alarm LED is no malfunction indicator. It has only the indicator function for the sensors.
The fridge goes in the normal operation mode when he passed the sequence. No further actions necessary.
Be aware that every time when the fridge faced a total power lost he makes a short silent 30s check sequence. If he face a malfunction (Sensors or actuators) he doesn't start the compressor anyway to protect the fridge for further damage!!! So, this test sequence is a nice tool to check that the fridge is in the right conditions to start the working and even so to check the compressor function before maybe a unnecessary replacement .
With a second build in test option you can select and activate devices in the fridge. For this You hold the fast freeze button and switch the fridge on. After 10s release the button and you are in a manual test mode. With the temperature button select the component - Push the Fast freeze button to activate or deactivate. For example: Select LED6 (Compressor) with the temperature button, push the fast freeze button for ON and OFF. But I ask You to be careful on this test mode to avoid further damages. For example a blocked motor that You should release better by hand than blow up by a tricky fingertip. Enjoy this fix and feel free for Crtl C + Crtl V.