Lenovo V15-IGL NM-D201 GV452/GV552 Turn on the power LED and nothing else

Hello everyone!
I have a Lenovo V15-IGL with NM-D201 GV452/GV552 motherboard, which when connecting the power supply, only the Power Led turns on and does nothing else.
With the motherboard removed, without battery and nothing connected (only motherboard), when connecting the power supply the consumption is 50mA.
I have measured the voltages in the coils and all the voltages are correct and present, except PL6601 (+CPU_CORE), where the value is 0V. I have measured the resistance with respect to ground: 40 Ω

I have measured the following voltages on PU6601:
Pin 7 (VCC)... 5V
Pin 11 (VSYS) ... 13,95V
Pin 52 (VIN_CT) ... 19,80V
Pin 16 (SYSON) ... 3,34V
Pin 15 (SUSP#) ... 3,34V
Pin 36 (ALW_PGOOD) ... 3,35V
Pin 27 (SYS_PWROK) .... 3,35V
Pin 45 (+VNN) ... 1,05V
Pin 24, 37 (+1,05VS) ...1,05V
Pin 26, 28 (+1,8VALW) ... 1,8V
Pin 18,21 (+1,2VALW) ... 1,2V
Pin 20 (Gate_VIN) ... 3,35V
Pin 19 (Gate VOUT) .... 2,48V
Pin 3 (+VTT) ... 0,59V
Is the value of pin 3 (+VTT) correct?

On UE1 I have measured the following pins:
Pin 11 (VCC)... 3,34V
Pin 26,50,92,114, 121 (+3VL_EC) ... 3,3V
Pin 74 (+3VL_EC_R) .... 3,3V
Pin 97 (EC_RSMRST#) ... 3,34V
Pin 82 (SYS_PWROK) ... 3,35V
Pin 98 (ALW_PGOOD) ... 3,36V

I initially extracted the SPI Bios (UC2) to make a backup copy, but during the reading, it gave me an error. The programmer recognizes the chip, but every time I try to read it, it gives an error.
I have changed it for a new one, and the new chip, when recording the dump, at the end has given me an error on 2 occasions. The third time it was recorded correctly. After soldering everything remains the same.

Zemog napisal/-a:The programmer recognizes the chip, but every time I try to read it, it gives an error.

Hello!
Which programmer do you use?

matic napisal/-a:Which programmer do you use?

TL866 II PLUS

EDIT: I have tested the programmer on another computer and I was able to read the BIOS without any problems.
I am going to program a new Dump from this new computer and I will test if there are any changes.

I have the exact one with the same problem. I also had problems with this chip, mostly during "Verify" phase on SVOD. After programming the BIOS, despite verifying failing, the chip was programmed correctly and the device works. The DMI section for this model is 483000 to 484FFFF.

tekort napisal/-a:The DMI section for this model is 483000 to 484FFFF

Do I have to copy the data from that section, from the backup to the new dump?

If you want to keep the original serial number you should copy this section from original one to the new dump. It is not mandatory, because device will work without it but in BIOS and in any Lenovo software the serial numbers will have a "INVALID" note.

Ok. Thanks a lot for the info, it's very useful for me

After reprogramming I have re-soldered the BIOS, but the problem remains the same. When I connect the power, the power led turns on automatically, and the consumption goes up to 50 mA.
If I keep the power button pressed (which is located on the keyboard), the power led turns off, but the consumption remains at 50 mA. As soon as I release the power button, the power led turns on again with the same consumption
Any suggestions?

Based on the symptoms you described, the communication between the KBC chip and PCH part (small core) of the APU hybrid is almost certainly missing.
Unfortunately, the APU hybrid is very likely damaged.

The laptop was finally returned. I'm closing the thread.