[LG Optimus 3D] KI-Shodan:
need help to unbrick

I can’t get my P920 to boot anymore.

When it still worked I wanted to flash it using the tool SmartFlash (link).

First it didn’t work, because while the „OMAP4430 USB device“ was found and I was able to install the drivers the LG modem device was never found.

So I tried to flash with Fastboot using omap4boot-for_optimus-v1.21 ( link), but this failed because I already got the error message „usb_read got: 0, expected: 4, errno: 121“ back then. But during the first steps before the error message appeared for unknown reason the LG modem was found, so that I was able to install its drivers.

Using Smartflash I was then able to flash firmware 2.3.5 - v21E (Germany) (used firmware link from this site). I had extracted the KDZ file for Smartflash using the P920/970 ROM Converter (link).

Afterwards my P920 worked with firmware 2.3.5. Only the battery was displayed as almost empty.

So I decided to flash firmware 4.0.4 – v30A (Euro Open) (used firmware link again from this site) using the same method. The flash process went flawless till the end. But now my P920 won’t boot anymore.

It doesn’t vibrate if I press a button a few seconds and no matter what I do nothing appears on the screen (this also applies to the next steps I’ll describe).

So I tried to follow the „[P920/5] [SU760] Resurrection Guide“ (link). But I can only follow it until step 7. My P920 still communicates with the Omap4boot tool and at the „OMAP4430 USB device“ device appears at the device manager, but after the line „waiting for 2ndstage response...“ only endless lines „usb_read got: 0, expected: 4, errno: 121“ appear. The LG modem isn’t found anymore, so I can’t use Smartflash anymore.

Her’s the complete Omap4boot log

--------------------------------------------
OMAP4boot for P920/P720/SU540/SU760/SU870
--------------------------------------------
by wkpark at gmail dot com

[1] cx2 - Optimus 3D Cube (SU870/P720)
[2] p920 - Optimus 3D (P920)
[3] p940 - Prada 3.0 (P940)
[4] su540 - Prada 3.0 (SU540/KU5400)
[5] su760 - Optimus 3D (SU760)
[x] exit
-------------------------------------------

Select device and <ENTER> 2
p920 selected

waiting for OMAP44xx device...

Device descriptor:
bLength = 18
bDescriptorType = 1
bcdUSB = 528
bDeviceClass = 255
bDeviceSubClass = 255
bDeviceProtocol = 255
bMaxPacketSize0 = 64
idVendor = 451
idProduct = D00F
bcdDevice = 0
iManufacturer = 33
iProduct = 37
iSerialNumber = 0
bNumConfigurations = 1
reading ASIC ID
usb_write 4
usb_read 81
[*] read 0 bytes
NumOfSubblocks: 0x5
Subblock ID: 0x1
Subblock Size: 0x5
CH enabled: 0x7
ROM revision: 0x2
Checksum Subblock: 0x15
CHIP: 4430
IDEN: 12bd240a5cbb4df74165e28847c766b87268a144
MPKH: 6d473e6a0470e01a52601081128b053b74490ee0000000000000000000000000
CRC0: 31b46fa0
CRC1: 611e8642
sending 2ndstage to target... f0030002
usb_write 4
usb_write 4

wait 5-seconds...

[*] msg size = 4
usb_write 21504
[*] data size = 21504
usb_close

Reopen usb...

Device descriptor:
bLength = 18
bDescriptorType = 1
bcdUSB = 528
bDeviceClass = 255
bDeviceSubClass = 255
bDeviceProtocol = 255
bMaxPacketSize0 = 64
idVendor = 451
idProduct = D00F
bcdDevice = 0
iManufacturer = 33
iProduct = 37
iSerialNumber = 0
bNumConfigurations = 1
waiting for 2ndstage response...
usb_read 4
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121
usb_read got: 0, expected: 4, errno: 121

I don’t have an external battery charger for the P920 battery. But a normal voltmeter shows a voltage of 4,0V for the P920 battery (since it’s a 3,7V battery it seems to me that it’s not empty at all).

I hope someone has an idea or knows how I can resurrect my P920.