HP 15-EH1070wm - Black Screen With Power LED.

[grimacelord]

Hello,

I have an HP 15-eh1070wm laptop that came to me for the same reasons I am starting this thread. The charging LED appears when the laptop power adapter is connected and the power LED appears when pressing the power button, but nothing appears on screen.

First thing I did was take off the bottom panel and remove the battery and then press and hold the power button for 30 seconds and then reinstall the battery and power on. The fan spins and this time, the back light illuminates and a brief message appears on the screen for about 1 second saying something along like, "BIOS upgrade is pending..." and I can't read the rest fast enough because the message disappears and the screen goes completely black. The fan continues to spin for a moment and then the fan stops spinning and it remains that way. The power LED continues to stay lit, but nothing ever appears on the screen and the CPU gets very hot.

Thinking it might be a corrupted BIOS, I took a BIOS dump and then reflashed the BIOS image that I extracted from the file I downloaded on HP's website for this model. I used a CH341A programmer with the 1.8V adapter because the BIOS chip uses 1.7-2.0V.

BIOS flashed successfully and I tested again and the laptop behaves the same way. Back light initially appears, 1 second message of pending BIOS update, screen goes black, fan continues to spin for a few more seconds and then stops, and then it remains that way forever until it is forced to shut down or power removed. I left it sitting like this up to 10 minutes thinking it might just be taking it's time, but nothing ever changes.

While I do think that this laptop has a BIOS issue, I am not so certain that is the ONLY issue this laptop has, but I am not sure. I was hoping someone could help me out here. I am attaching/listing any information that I think would be important below. Thanks.

Model: HP 15-eh1070wm
Motherboard model: DAG7HAMB8F0 REV:F | MODEL: G7HA
BIOS IC: GigaDevice GD25LQ128ESIGR
CPU: AMD Ryzen 7 5700U

Couldn't find schematic for this particular board...thanks again.

[mon2]

Re: HP 15-EH1070wm - Black Screen With Power LED.

Hi. You are working with the main bios. There may be a secondary bios near the EC controller which is usually based on a 8051 microcontroller architecture.

That is, if you can locate it, the issue may be with that device.

If present, read and archive the contents -> verify the contents you have read from that device are 100% correct / same density as the device, etc.

Then erase that device and solder it back to test again.

Some of the boards will use the main bios to reflash the secondary firmware for the EC device.

Some EC controllers require to be reflashed using the KBC pins with an external tool like SVOD.

Just throwing out some ideas to consider while waiting for others to comment.

[grimacelord]

Re: HP 15-EH1070wm - Black Screen With Power LED.

Hi. You are working with the main bios. There may be a secondary bios near the EC controller which is usually based on a 8051 microcontroller architecture.

Hi. Thanks for the reply. The chip I am working with now is right next to the EC.

However...I just now discovered a MX25L8006E next to CPU. Datasheet: https://cdn.badcaps-static.com/pdfs/...1b5ea0e8f1.pdf

Let me take a look at that while I wait for any other suggestions...

EDIT: Attached is dump from that chip, but I don't know if its even relevant.

[grimacelord]

Re: HP 15-EH1070wm - Black Screen With Power LED.

Hmm. So while I was troubleshooting, I discovered that if the battery was not connected, then the computer would POST and boot the OS fine. If the battery was connected, then it behaved as how I described in this thread. I measured the voltage of the battery and it was fully charged, so I suppose it's somehow defective. New battery on order. Will update after I replace it.

[hoaca388]

Re: HP 15-EH1070wm - Black Screen With Power LED.

Hmm. So while I was troubleshooting, I discovered that if the battery was not connected, then the computer would POST and boot the OS fine. If the battery was connected, then it behaved as how I described in this thread. I measured the voltage of the battery and it was fully charged, so I suppose it's somehow defective. New battery on order. Will update after I replace it.

HP Pavilion 15.6 inch Laptop PC 15-eh1000 (2H5A7AV)

[grimacelord]

Re: HP 15-EH1070wm - Black Screen With Power LED.

New battery fixed it, although I believe the BIOS was initially corrupted so it did still need to be reflashed. Solved!

[abbassink]

Re: HP 15-EH1070wm - Black Screen With Power LED.

Hello,

I have an HP 15-eh1070wm laptop that came to me for the same reasons I am starting this thread. The charging LED appears when the laptop power adapter is connected and the power LED appears when pressing the power button, but nothing appears on screen.

First thing I did was take off the bottom panel and remove the battery and then press and hold the power button for 30 seconds and then reinstall the battery and power on. The fan spins and this time, the back light illuminates and a brief message appears on the screen for about 1 second saying something along like, "BIOS upgrade is pending..." and I can't read the rest fast enough because the message disappears and the screen goes completely black. The fan continues to spin for a moment and then the fan stops spinning and it remains that way. The power LED continues to stay lit, but nothing ever appears on the screen and the CPU gets very hot.

Thinking it might be a corrupted BIOS, I took a BIOS dump and then reflashed the BIOS image that I extracted from the file I downloaded on HP's website for this model. I used a CH341A programmer with the 1.8V adapter because the BIOS chip uses 1.7-2.0V.

BIOS flashed successfully and I tested again and the laptop behaves the same way. Back light initially appears, 1 second message of pending BIOS update, screen goes black, fan continues to spin for a few more seconds and then stops, and then it remains that way forever until it is forced to shut down or power removed. I left it sitting like this up to 10 minutes thinking it might just be taking it's time, but nothing ever changes.

While I do think that this laptop has a BIOS issue, I am not so certain that is the ONLY issue this laptop has, but I am not sure. I was hoping someone could help me out here. I am attaching/listing any information that I think would be important below. Thanks.

Model: HP 15-eh1070wm
Motherboard model: DAG7HAMB8F0 REV:F | MODEL: G7HA
BIOS IC: GigaDevice GD25LQ128ESIGR
CPU: AMD Ryzen 7 5700U

Couldn't find schematic for this particular board...thanks again.

your bios is damaged
it's 100% working

[denilloo]

Re: HP 15-EH1070wm - Black Screen With Power LED.


your bios is damaged
it's 100% working

Thank you. This BIOS work for me