help me diagnose and fix TV, monitor (and if possible laptop as well)

I will give you all the details that I have on the item along with what tests I have done. You will tell me what to check and what else to do. I will do so. you will let me know what to change or how to fix it and I will do that.
The project is complete when the TV, monitor, or laptop is fixed.

Let me know if you can help with the TV and monitor or laptop as well.

Basic fault:
Monitor : Led keeps blinking does not turn on model Mango QHD 397. For this one it is giving 23V at the 12V output.

TV Model 40K321UW no led does not turn on. The power supply is giving 3.3V standby voltage on the 12V line but this 3.3v is seen in a few places on the motherboard but does not reach the eeprom or the point marked 3.3v on the motherboard.

Laptop: Dell Inspiron 3480 no led does not turn on. The power supply is giving 19V. I have the schematic for this (brd file) and the associated pdf file. I will give it to you.

You must have experience with doing these types of repairs. please do not bid if you do not have experience.

Put a bid and I will chat to give more details. Put your bid for one of the three and let me know which one it is.
Thanks