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[HOW TO] Unbrick your LG P500 Optimus One

Discussion in 'Android Devices' started by Gremaldin, Sep 8, 2011.

  1. Gremaldin

    Gremaldin Well-Known Member
    Thread Starter

    Disclaimer: I will not be responsible for anything that happens to your phone after following this post. You are doing this because you choose to and you alone are responsible for anything that may happen. Use at your own risk.

    In this method, you are doing a full wipe of your phone including ROM and force flashing everything from scratch. So there is a risk of permanently bricking you phone (i.e. your phone will look just like it doesn't have a battery and you can use it as a very expensive paper weight). If you have already rooted, installed a custom recovery and you are able to boot to custom recovery, then I do not recommend using this method (though it will work just fine). If you can boot into recovery, restore a previous backup or flash a new ROM or reflash your current ROM - no matter how many times you try to flash from recovery, you will never brick your device (i.e. it is a safer method).

    Please not that since this method does a complete wipe, you will loose root, custom recovery etc. You can still root again after you fix your phone. For those who haven't rooted, just ignore that.....

    NOTE: This should work for any screen you are stuck at. I'm just mentioning the screens I have come across.

    If your phone is stuck at the LG/Android boot screen or emergency mode or a black screen saying

    fastboot mode started

    then your phone isn't bricked, you dont need to panic. Your phone can be fixed right at home by following these steps.

    After doing some research, I found that

    fastboot mode started

    is displayed when we do something like install custom recovery and failed.

    There may or may not be additional lines of text, but the procedure is the same for all such cases where the starting 2 lines are the above.

    1. Download KDZ Updater and LG united mobile drivers from here.

    2. Extract the rar file and install LG United mobile drivers.

    3. Disable all LGE modems under modems from windows device manager.

    4. Charge your phone since we cant really tell how much juice is left in the battery even though the screen is on.

    5. Download the stock firmware (also known as rom) from Lg’s firmware repository. You can download the firmware and firmware version suiting your region from the links I have provided below. But many of these links may not work, so to download the stock 2.2.2 ROM build V10D_00 for India, click here. If you choose to download this stock ROM, then ignore Methods 1 & 2 given below. If however you want to download a ROM for a different country and version, then follow Method 1 or 2.

    Method 1:

    The following link will list all the country codes for LG optimus p 500.


    Press ctrl + f on the keyboard to bring up the browser search tool and type the name of your country.

    Copy your country’s code. For example for india its AINDBK. Now paste it in the url below where it is marked XXXXXX.


    Your link would look something like this after pasting the code


    Replace the V10b_00/V10B_00.kdz with the version number you want. For example if i want to install version 10C then i would change the letters from c to b like this V10c_00/V10C00.

    Now copy and paste the link in the addressbar of your browser and press enter key. Download should start.

    This method may not work for all countries.

    Method 2:

    If the above method didn't work (it didn't for me), then here’s a list of the latest unbranded firmware as of 9/03/2011 4:15 EST

    Just click on the links below to start the DOWNLOAD

    [ROMS] Original LG Firmware list - Page 18 - xda-developers
    Newest found : http://csmg.lgmobile.com:9002/swdata/WEBSW/LGP500/AAUSBK/V10b_00/V10B_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10E_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10F_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10H_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10E_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10H_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10A_00.kdz

    LGP500 – AGLOBK – GLO/Philippines GLO
    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10B_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10H_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10B_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10H_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10D_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10D_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10E_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10H_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10A_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10F_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10H_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10E_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10F_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10F_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10D_00.kdz

    LGP500 – ASWSBK – SWS/Switzerland
    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10D_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10F_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10C_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10F_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10A_00.kdz

    Newest found : http://csmg.lgmobile.com:9002/swdata…00/V10A_00.kdz

    6. Install msxml (from the KDZ Updater folder) on your windows pc by double clicking it.

    7. a. If your phone is stuck at the Android screen or LG screen or Emergency screen, connect your phone to your PC via USB.

    b. If your phone is stuck at fastboot mode started udc_start() screen, then remove the battery and reinsert it. Now press the back key and volume up button and simultaneously connect your phone to your PC. You will get a greenish yellow screen saying Emergency mode.

    8. Run KDZ_FW_UPD.exe with administrator privilages (right click, run as administrator in win7).

    9. In the software window, select Type as 3GQCT
    Select PhoneMode as "DIAG" if your phone is not in emergency mode (i.e., if your phone is in LG/Android screen). If you are in emergency mode, select "Emergency".
    In the place where you have to give path for KDZ file, select the Firmware a.k.a ROM you have downloaded using the link you made for your country specific firmware.

    10. Press Launch software update and wait for about 10 or 15 minutes. The screen will then say “Emergency mode”. Just wait and let it reboot. Do not disconnect your phone till it is shown "finished".

    11. Now switch on your phone. Finished!

    [OPTIONAL] Hit the thanks button!

    Note: If kdz is unable to see your phone, then try running kdz in compatibility mode for XP, restarting your phone, shaking your phone (I know it sounds crazy but it works sometimes!), restarting your computer, try and try again till it works.

    NOTE: If KDZ stops working and phone gets stuck in recovery mode and you have to remove the battery just to turn off the phone, and you cant get into recovery mode or emergency mode, but you're stuck at a black screen, remove the battery and connect the phone via USB to a computer which has LG United mobile drivers installed. Disable all LGE modems under modems from windows device manager.

    Unplug the usb cord from your PC and plug it in again. You still shouldn't have a battery in your phone, yet by plugging it in the "Emergency mode" should start automatically. Open up KDZ, select Type "3GQCT" and PhoneMode "EMERGENCY". Select a KDZ file and flash it.

    NOTE: If your phone doesn't even turn on, the try holding back + vol up + power and simultaneously connect to a computer which has LG United mobile drivers intstalled via USB. Then you should reach emergency mode. Then just follow the steps mentioned above.

    1. Download the Forums for Android™ app!


  2. mryum

    mryum Lurker

    excellent guide, saved me after a failed LG Updater update.

    however, you may need to hardware reset your phone with VOLUMEDOWN+HOME then POWER to turn it on. keep holding VOLUMEDOWN+HOME until the android logo + open box shows on the screen (after the LG logo) then you can let go and watch your phone boot *rejoice*

    this will factory reset it
    quesiaboagye likes this.
  3. Gremaldin

    Gremaldin Well-Known Member
    Thread Starter

    Yes, we can recover our phone from recovery mode too, but this works even if we cant boot to recovery. For some reason, I wasn't able to boot to recovery. In fact it was when I tried to boot to recovery that I came across the "fastboot mode" screen and got stuck.
  4. seanicus

    seanicus Lurker

    Hi there my phone is doing the thing fast boot thing but i cant seem to download the KDZ files from the links if anyone could download the Australian one for me and send it via Email i would love you for ever.
  5. Gremaldin

    Gremaldin Well-Known Member
    Thread Starter

    Heres a suggestion.... download the Indian firmware, get your phone in working order.

    Then if you want to keep the stock version, then uninstall those silly indian apps, install any system apps you miss from your Australian version and keep it.... :p

    Or, install another custom ROM and never look back at the stock one. :D

    EDIT: I've updated the link. Its working now.
  6. nokal

    nokal Lurker

    thanks again Gremaldin .my phone LG P500 work again.i m using ROM from india.i try so many times at last i made it .i from singapore anyway u save my phone thanks again.
  7. I can't make this work. I even read a similar guide to use windows enabler to make the KDZ updater work, it is greyed out and it will not let me use it even as administrator.
  8. Aristotel

    Aristotel Lurker


    I've done these steps but my LG Optimus One P500 is still stuck at the Android screen.
    My problem occurred after I've upgraded the firmware from 10C to 20H using LG PC Suite IV (the button Check update). After the upgrade was complete the phone remained at the Android screen.

    Can someone give me some suggestions about how to solve this problem please?

    Thanks in advance!
  9. billyjack70

    billyjack70 Lurker

    after 5 days, this is what i found that finally worked ....thanks
  10. Deepakhiman

    Deepakhiman Lurker

    Thanks Gremaldin! Superbly written.

    Now that I have re-bricked, the only issue is my SD card contents are not getting 'read'. I had installed most of my market apps there. How do I recover that back?
  11. Deepakhiman

    Deepakhiman Lurker

    Am reinstalling from titanium backup after rooting.
  12. scary alien

    scary alien not really so scary
    VIP Member


    Since this appears to be related to root activities, I've moved it to the all-things-root sub-forum for you.

    Thanks to the OP for the great write-up and contribution :).

    AndyOpie150 likes this.
  13. pkosta

    pkosta Lurker

    just wanna says thanks fixed my ph when the update with lg sw update failed
    this got my ph working again using emergency mode
  14. pkosta

    pkosta Lurker

    Happydave123 likes this.
  15. Happydave123

    Happydave123 Lurker

    I had used the KDZ tool before to restore my p509 to stock, but I thought I bricked it after flashing an Oxygen mod, then tried to update to 2.0 baseband. I think I had forgot to disable modems in device manager. Was about to trash it when I came across your post. You are right! If you keep trying you can resurrect it. If you are here in desperation don't give up! In my case I reinstalled the drivers 2 or3 times before KDZ would see it in emergency mode, but finally it did.

    Thanks Again!!!
    scary alien likes this.
  16. quesiaboagye

    quesiaboagye Lurker

    Your solution worked for me.
    scary alien likes this.
  17. qammar61

    qammar61 Lurker

    Thanks you very much. Your method worked for me and now my LG P500 is alive again.

    scary alien likes this.
  18. asarangan

    asarangan Lurker

    I followed this procedure on my P506, got the phone into Emergency mode. But the program fails with "Upgrade Error, WParam:100, LParam: 4008."

    Now my phone only boots into emergency mode.

    The logfile is shown below:

    18:51:58 : Launching SW update
    18:51:58 : Unpacking KDZ
    18:51:59 : KDZ file extraced
    18:51:59 : Files were extracted.
    18:51:59 : LGMobileDL Load.
    18:51:59 : Port = -1
    18:51:59 : Connecting to phone
    18:52:09 : Check Phone mode = 1
    18:52:27 : Phone type check.......
    18:52:32 : LGMobileDL.DLL Loading....
    18:52:32 : _SetAuthMark Fail
    18:52:32 : AuthMark
  19. anshul_666

    anshul_666 Lurker

    I also followed the steps you've mentioned above but still nothing for me. :(
    I installed CM on my phone two days ago and it was well working but when I tried to install Gapps package onto my phone then during the final reboot the LG logo kept flashing for so long. I waited but nothing happened and finally I removed the battery and turned my phone on but all I can see now is the LG logo only. Can you please suggest me what to do next. :(
  20. Juan del Pino

    Juan del Pino Lurker

    Best Tutorial that has worked for my lg p500! Thanks a bunch..:)
    scary alien likes this.

LG Optimus One Forum

The LG Optimus One release date was October 2010. Features and Specs include a 3.2" inch screen, 3MP camera, 512GB RAM, Snapdragon S1 processor, and 1500mAh battery.

October 2010
Release Date

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