Troubleshoot led display

Hello guys!

I would like to ask for some help i have got a digital Exhaust gas temperarure display.
Today it started acting up, when i put 12V on it it just shows me a number 4 and its just flashing sometimes it reads the temperature but flashing sometimes go black.
How can i troubleshoot this device?
https://www.imageupload.net/image/Dyx5O
https://www.imageupload.net/image/Dy3sk
https://www.imageupload.net/image/DyeCp

Thanks!

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No idea! :roll_eyes:

Can't distinguish the numbers on the chip. :astonished:

Hello thanks, cheap aliexpress thermometer doesnt matter but maybe if i can fix that would be nice :smiley:
If any1 got idea let me know!

Thanks!