Lenovo E570 NM-B421 Turns on then off.

[sikocan]

Can I please get some help, I can't figure this out.

Board: NM-B421
Model: Lenovo ThinkPad E570

Charger plugged in, flashes 3 times. Power button pressed, it turns on 2 seconds then off. Occasional fan spin slightly until it turns off again. Never more than 2 seconds.

Attached PDF shows readings I gathered.

Things tried:
Flashed 5 different BIOS files, original bios dump + 5 others linked, schematics and board readings are all here:
https://drive.google.com/drive/folde...US?usp=sharing

Here is the video of the fault:
https://youtu.be/OB6xf7211Mg

Aditya11ttt says on a forum:
'In this board u don't need to program io it will program auto , but still it's a theory u should try to program and update me it's done or not !!"

Attached also the image of the board with readings.

Anything else I can try? Thanks!

[sikocan]

Re: Lenovo E570 NM-B421 Turns on then off.

PQ301 Mosfet is playing weird. I've replaced the Mosfet already. The PU301 which is a RT8231AGQW is acting up I suspect. See measurements.

[sikocan]

Re: Lenovo E570 NM-B421 Turns on then off.

Sorry this is the correct readings.

[z2168235]

Re: Lenovo E570 NM-B421 Turns on then off.

I had similar experience with HP laptop, on 1-2 seconds and then off again. All voltages are present. Scratching head for a while before I discover the issue is due to faulty DRAM. Not sure if you have try replace the DRAM with known good DRAM.

[sikocan]

Re: Lenovo E570 NM-B421 Turns on then off.

You mean Dram controller? Ram is replaceable. Tried different ram.

[ajbernasko]

Re: Lenovo E570 NM-B421 Turns on then off.

Can I please get some help, I can't figure this out.

Board: NM-B421
Model: Lenovo ThinkPad E570

Charger plugged in, flashes 3 times. Power button pressed, it turns on 2 seconds then off. Occasional fan spin slightly until it turns off again. Never more than 2 seconds.

Attached PDF shows readings I gathered.

Things tried:
Flashed 5 different BIOS files, original bios dump + 5 others linked, schematics and board readings are all here:
https://drive.google.com/drive/folde...US?usp=sharing

Here is the video of the fault:
https://youtu.be/OB6xf7211Mg

Aditya11ttt says on a forum:
'In this board u don’t need to program io it will program auto , but still it’s a theory u should try to program and update me it’s done or not !!"

Attached also the image of the board with readings.

Anything else I can try? Thanks!

anyone fixing this issue and stuck at this point of reading should check if the cpu pwm NP81218 is receiving the 5V (vcc) on pin#13, if not measure for short or replace ic.