Dell Latitude E5550 FW status recovery error & unable to reboot

[a_tiny_ant]

Hi everyone

Since a month or so my laptop, a refurbished Dell Latitude E5550, has been unable to exit sleep mode or properly reboot. Upon waking from sleep mode it shuts down and reboots and upon attempting a reboot it just hangs at a black screen forever. The laptop was working fine for several years up until a month ago.

Initially I thought it was OS related, since it's running Arch Linux, wouldn't be the first time an update broke something but it also happens on Windows, Ubuntu live images and even a complete restored image from a year ago where it definitely worked fine.

Upon booting the message "FW Status recovery error" is visible and in the boot menu I'm unable to enter the MEBx extension menu. It just reboots then and afterwards the MEBx extension menu disappears from the boot menu.
Apparently the FW error is caused by a corrupted Intel Management Engine according to some threads found on Google.

In the BIOS there's no way to disable MEBx, it's only possible to disable hotkeys or menu entries from here. I've never used any of these functions and they're better off disabled, but they never caused any issues either up until now.

The CMOS battery is not the issue, I've replaced that already but it wasn't even necessary according to the batteries' voltage.

Now the most annoying side effect, flashing a new BIOS which could fix the issue does not work because it requires a reboot, which at this moment the laptop is unable to do.
Perhaps it's possible that a MOSFET on the mainboard, that controls power states, is somehow fried? Is there any proper way to figure that out according to the schematics?

Is it possible to reflash the BIOS and/or MEBx part from either Linux or Windows that doesn't require a reboot?

Thanks!

[SMDFlea]

Originally Posted by a_tiny_ant

Is it possible to reflash the BIOS and/or MEBx part from either Linux or Windows that doesn't require a reboot?

Thanks!

Its the ME firmware thats corrupt.You can try flashing the bios from windows, it will/should update the ME firmware https://dl.dell.com/FOLDER06331241M/1/E5550A24.exe .

Be warned though,the update could go wrong,and then you`ll need to flash another bios with an SPI programmer.

[a_tiny_ant]

Originally Posted by SMDFlea

Its the ME firmware thats corrupt.You can try flashing the bios from windows, it will/should update the ME firmware https://dl.dell.com/FOLDER06331241M/1/E5550A24.exe .

Be warned though,the update could go wrong,and then you`ll need to flash another bios with an SPI programmer.

Thanks but that is the one thing that didn't work. That executable forces a reboot which then gets permanently stuck. Also running it from the boot menu, or even FreeDOS, they all require a reboot before the bios is flashed.

I've also tried extracting the BIOS bin files using Dell_PFS_Extract and that produces 10 different bin files. I assume the BIOS needs to be flashed with one BIN file if using an SPI programmer right? It looks like it will have to be done this way.

[SMDFlea]

Originally Posted by a_tiny_ant

Thanks but that is the one thing that didn't work. That executable forces a reboot which then gets permanently stuck. Also running it from the boot menu, or even FreeDOS, they all require a reboot before the bios is flashed.

I've also tried extracting the BIOS bin files using Dell_PFS_Extract and that produces 10 different bin files. I assume the BIOS needs to be flashed with one BIN file if using an SPI programmer right? It looks like it will have to be done this way.

The extracted files are only ME FW and a bios update.If you make a backup post it in the Bios requests section and someone will repair it

https://www.badcaps.net/forum/forumdisplay.php?f=40

[a_tiny_ant]

Right. I have extracted the BIN files from the executable, not my actual BIOS yet.
I haven't identified the correct chip yet from the boardview/schematics yet.

Is there an easy way to tell which one it is? There are two 8 legged Winbond chips that are connected to the CMOS battery, however one of them is for 32bit and the other for 64?

[SMDFlea]

Originally Posted by a_tiny_ant

Right. I have extracted the BIN files from the executable, not my actual BIOS yet.
I haven't identified the correct chip yet from the boardview/schematics yet.

Is there an easy way to tell which one it is? There are two 8 legged Winbond chips that are connected to the CMOS battery, however one of them is for 32bit and the other for 64?

Both of them,the bios is split across both chips. Make a backup first, then flash both of the bios at post #23 https://www.badcaps.net/forum/showth...t=65154&page=2