MSI Katana GF66-12UC - don't turn on

[tehmatix]

MSI Katana GF66 12UC-873XES-BB51245H16GXXDXX, motherboard model is MS-15821 ver 2.0, bios chip model is MX25L25673G, serial number is K2304N0140517

1. When its connected to power supply (battery is disconnected), the consume is 22mA for 2 seconds and then 88mA, without to press power button, and stay on this state forever.
Main power rail is present 19V, and other voltages on the board 3.3V, 5V, 1.8V. Memory voltage missing. No fans spinning. I checked with thermal camera only PCH (nud FH82HM570 SRKMA) is warm (32* C).
Its doing same thing when the board is not connected with other peripherals (keyboard, screen, M2 hard, memory, wifi card).

2. Internal battery connected, when power button is pressed on the board I get : main power rail 12.50V (battery voltage), 3.3V, 5V, 1.8V , present for 5 second and turn off.

Please see attached photo with resistance measurement of the coils.

Any advice will be helpful

Thank you

[mcplslg123]

The coil located close to left fan topside seems like VRAM. Confirm whether this coil is indeed for VRAM power.

If its true, then something is definitely wrong here.

[tehmatix]

Yes, those cois are for VRAM and video chip. I have isolated them from the system by lifting those coils. I got the same problem.

[mcplslg123]

If indeed its a VRAM coil then its supposed to be 1.2/1.35V. After removing the coil ,whats the resistance to GND on both pads of this coil?

Your VRAM may be shorted.

[tehmatix]

On the mosfet side it is more than 2 kohm, on the VRAM side it is 0 - 0.1 ohm.
If the VRAM and graphics chip are not powered (coils are lifted), should the laptop start?
What would be the boot sequence of the laptop ?

[mcplslg123]

Very likely yes. Just disconnect the coils powering GPU+VRam and it may boot from Intel integrated graphics.

[tehmatix]

I disconnected the GPU+VRam coils, but the laptop still doesn’t turn on. I believe that there is a problem with the EC chip KB9548QF2. If I would replace the EC chip, do I need to program it as well? Or will the BIOS program it automatically?

[mcplslg123]

The EC is programmable for sure but dont know whether it gets auto programmed on MSI platform.

Nothing so far indicates a damaged EC-so why change parts in haphazard manner.

Go deeper in diagnosing the issue. Patience is the key besides knowledge.

[tehmatix]

What is your options for the next step?

[mcplslg123]

Schematic available? If yes link it

[tehmatix]

I don’t have a schematic for this, trying to find one. Only boardview.

[christian100]

i have same issue but always have 3,3v and 5 v i hat damage ec chip after replace i get 30mma and then 80mma without starting the laptop. I think in your case it could bei the EC you mus buy programmed ec and extract ec firmware from msi side. can you please send me your boardview because i also need firmware.
And first of all you schould describe your mistake history so why laptop is demage by me customer has made short with screwdriver

[christian100]

i need help in Programming KB9548QF2 in youtube i found video to programm this with CH341A i had laptop gF76 katana msi . Do you think it can programm with CH341A this chip or can any person give me help to do this?
thanks for answering.