GSM-Forum - View Single Post - Can I downgrade lg gt540 from v20 to v10 ??

Octopus box · 07-02-2012, 16:26

Hello.
We don't recommend to downgrade firmware version in your GT540 phone if You have no Jtag tool, because during of downgrade process phone's boot can be damaged, so You will need to repair it via Jtag. If You have Jtag tool You can try to downgrade. To do this please perform the next steps:
1. Select "Write boot loaders" option and select "GT540AT-00-V10c-ARB-XX-SEP-02-2010" firmware.
2. Press "Write firmware" button.

Note! If the error occurs during writing (AMSS or another part of firmware), YOU MANDATORY NEED to disconnect the cable, reconnect the battery, MANUALLY put phone into emergency mode (press and hold "Vol+" + "Vol-" + "Power"), connect the cable and repeat the procedure of firmware writing. It is very IMPORTANT to put the phone into Emergency mode MANUALLY!

Also please clean your PC - uninstall all modem dashboard software, PC suite software, BB software. The best way is to use totally cleaned PC (only OS installed and drivers). Please don't use any USB hubs - use motherboard USB ports only!

07-02-2012, 16:26	#2 (permalink)
Octopus box Product Supporter Join Date: Oct 2009 Location: Romania, Bucharest Posts: 99,837 Member: 1146942 Status: Offline Sonork: 100.1587278 Thanks Meter: 27,411	Hello. We don't recommend to downgrade firmware version in your GT540 phone if You have no Jtag tool, because during of downgrade process phone's boot can be damaged, so You will need to repair it via Jtag. If You have Jtag tool You can try to downgrade. To do this please perform the next steps: 1. Select "Write boot loaders" option and select "GT540AT-00-V10c-ARB-XX-SEP-02-2010" firmware. 2. Press "Write firmware" button. Note! If the error occurs during writing (AMSS or another part of firmware), YOU MANDATORY NEED to disconnect the cable, reconnect the battery, MANUALLY put phone into emergency mode (press and hold "Vol+" + "Vol-" + "Power"), connect the cable and repeat the procedure of firmware writing. It is very IMPORTANT to put the phone into Emergency mode MANUALLY! Also please clean your PC - uninstall all modem dashboard software, PC suite software, BB software. The best way is to use totally cleaned PC (only OS installed and drivers). Please don't use any USB hubs - use motherboard USB ports only!