EuropAce EWC 913 Wine Cooler power board fuse blow /shorted

[beetle1303]

Hi,
I am a occasional hobbyist home electronic / electrical goods repairer without formal training in electronics/electricity. I learned from here and Youtube mostly.
I was given a EuropAce wine cooler model EWC 913, with no power supply - totally dead.
I opened up everything, and zoom into the power supply board (see attached pics), the board part# is Hanny10-12b, PCB110729M1, Rev0.
There are 2 fuses, 1 is OK, 1 was burnt. I disconnected all the input and output cables, put the power board stand-alone on a table, and replaced the burnt fuse. I burnt immediately upon power-on.
After reading some discussions in this forum, I followed 1 of the suggestions:
- I wired 2x40w incandescent bulbs in series with the live wire going to the board, temporary soldered a thin wire across the blown fuse.
- When power on, both the incandescent bulbs lights up and stayed lighted up until I power off. Based on what I read, this is a clear indication of a short-circuit somewhere.
I do not know how to read / trace circuit board, so I practically did a process of eliminations by removing all the capacitors and diodes to test using a DMM, and when the tests appeared good, I soldered them back. I repeated this process with all the transistors. As for resistors I only tested then in circuit. I even removed the 2 big blue and black rectangle parts (presumably relays). But doing all this has no effects at all on the 2 bulbs - they always lighted when I power on. The last I tried was removing the transformer - then the 2 bulbs di not light up!
While doing all these removing/restoring, I only occasionally checked the incoming voltage at the 2 input terminal - it's quite consistently at around 5V. I did not take any reading beyond this.

Please kindly help with my journey to debug and find the short circuit.
Thank you very much.