W520 doesn't boot after critical battery error...

[salzrat]

My beloved W520 doesn't boot anymore.

I had a power supply with a failing id-pin (i.e., I had to connect 5-10 times until the PS was recognized as 170W adapter and charging started). After some repairs and moving the PS, this didn't work anymore, and while trying, the battery went low and I got a "critical battery failure" error.

I then found a good 170W power supply (both 20V and the id PIN are electrically verified to work), but now the W520 doesn't boot anymore.

I removed the battery, but the only thing it does is light up the keyboard, keyboard light and some status lights, spin up the fan for 3-5 seconds, and then power down again. The LCD screen doesn't come to live at all.

I tried removing everything (HDD, RAM, ...), pressing the power button 60s with and without power supply connected, to no avail. I also disconnected the CMOS battery, still no luck.

When I remove all the RAM, it starts with the 1-3-3-1 beep sequence, complaining about the missing RAM, and then powers down, so in principle something is still working properly.

Is there anything else I can do? Or is the mainboard toast, and if yes, why?

Any help is greatly appreciated!

[axur-delmeria]

I also encountered a similar critical battery error on my X220 before it died. I reckon some part of the power circuitry gave out. Given that these are 15 year old laptops, that's not unexpected (even though my 20 year old X60s is still running).

[salzrat]

That would be a pity - the W520, especially with the Quadro 2000, is such an amazing machine. It can still be used to play Minecraft and Roblox without major problems!

[axur-delmeria]

If there's a laptop repair shop nearby, you could ask how much it would take to repair the board (if possible).

[salzrat]

So you would assume the board is shot?

I found a replacement board or 85USD, which is very likely less than a repair, but likely also worth more than the current value of the device...

[axur-delmeria]

So you would assume the board is shot?

Yes, since you mentioned that the laptop powers down by itself after the 1-3-3-1 error beep. In my experience, a 1-3-3-1 error beep will loop endlessly until you turn off the laptop.

[salzrat]

Through some other help, the most likely culprit is now the EEPROM chip. One option would be to try to reprogram it. Does anybody have the necessary files for a W520?

[axur-delmeria]

Through some other help, the most likely culprit is now the EEPROM chip.

That's interesting. I remember there was an old issue with the X220 that involved the EEPROM chip (though I can't recall the details), though I wonder if it's the same issue as in your W520. If it is, then you may need to replace the EEPROM chips themselves.

[salzrat]

Exactly, in the german Thinkpad Forum there is a thread on that, but in that thread, people with the same symptoms were able to fix it by reflashing the EEPROM. But without the correct file, I can't even start planning a flash...

[RealBlackStuff]

See if this helps: https://www.alisaler.com/lenovo-thinkpa ... -bin-file/

[salzrat]

New developments: I measured the Bios chip and it receives 3.3V in PIN8, and also the requests on PIN1.

Then I reassembled everything and tried to start the laptop again with only the battery, and it booted into bios and threw the critical battery error again! So by lying around for a couple of days the battery seems to have recovered so far that it was possible to boot at least that far. But that tells me Bios, CPU, GPU and so on are in principle fine.

So either for some strange reason my third power supply is broken as well, or something in the id pin detection on the motherboard is broken. Any ideas? I don't think the power supply is bad, I'm measuring 20V, and 1.5KOhm on the id pin, which should be correct...

[salzrat]

See if this helps: https://www.alisaler.com/lenovo-thinkpa ... -bin-file/

thanks, but I think this is just if you lose the bios password...

[RealBlackStuff]

Check this for help with any other working battery: viewtopic.php?p=680106#p680106