Reasons you might flash a phone with different firmware:

Flashing the firmware is a procedure that might be done for the purposes of fixing bugs in the software of the phone, or perhaps adding features.

If you have a G5300, it seems the G5300i firmware is compatible. Loading the G5300i firmware may enable features of this model on the older model.

There is a risk associacted with firmware updates. Normally, the firmware is erased first before it's updated. This process is therefore dangerous and could cripple the phone. If it's not done by an authorised dealer then I expect that it would also void any warranty you may have on the phone.

The information is provided for interest only. Do not follow these steps using your own (or someone elses!) phone. If you damage the phone, it's your own fault.

After making sure the phone was fully charged, the procedure I used for flashing the firmware on my phone was as follows:

1. Determine the version of your phone
Apparently, there are some phones that have 40-voice polyphonic sound, and some have 16-voices. On my phone, the serial number under the battery ends in "-P16".. and therefore it's a 16-voice model. To double-check, type 2945#*01# into the phone. This will open up a hidden menu called 'ENG MODE'. Scroll up and select 'S/W Version' and you should see a string similar to G5300P16-xx-xxx-xxx. The P16 here verifies that it's a 16-voice version.

2. Obtain the firmware for the phone
Since I wanted to try to update my G5300 to a G5300i, I needed to find the G5300i firmware somewhere. For some reason the russian web sites seem to be full of this stuff.. One such site is mobileclub.com.ru. The firmware I used is here.

You might be able to take a backup of the firmware that's currently in your phone. The floader program (below) is mean to be able to do it, but I couldn't get it to work... so I went ahead without it.

3. Obtain the flash software
To flash the phone, a copy of 'floader V2' is needed. The version I used is here.

4. Backup your phone's calibration data
Even though electronic devices may be made using identical components, there is always differences between one device and another. This is due to tolerances in the components used - it's simply not possible to create exact copies of an electronic device. Therefore every device needs to be tuned or calibrated to try and overcome these differences. The mobile phone is no different.

The phone contains calibration data that it needs in order to operate at peak efficiency. Using floader, I back up the calibration data to disk using the 'read cal data' feature:

There's an undocumented feature of this tab. The '...' button doesn't work as expected. Simply click inside the 'File' text box and manually type in the path and filename. It might be best to make it short - ie: c:\caldata.bin would be a good choice.

I plugged the data cable the phone came with to COM1, turned the phone OFF and connected the data cable to the phone.

After clicking 'Start' on floader, I was prompted with the message "Power on / reset target". This simply means to press the power button on the phone. The important thing is to not let go of the button! It must be kept held down until floader is finished!

It only takes a couple of seconds to backup the calibration data. When it has finished, unplug the phone and remove the battery, then re-install the battery.

5. Erase the current firmware
This is where the fun starts. You might like to backup the address book first, and any settings that you need. Erasing the firmware will also erase everything out of the phone.

I selected the 'Erase' tab in floader. In the 'Model' drop-box, select '5300'. The remainder of the details are filled in automatically by the software.

To save me from holding the power button in for ages, I worked out how to rest one of my speakers on the phone. I've heard other people use clothes pegs. Since a flash can take 20 minutes, I had to find a way to hold the power button in!

I then plugged the phone back into the cable, pressed 'start' in floader, and pressed the power button on the phone (and kept it pressed in!). The erase takes a short while, the software indicates when it has finished. Note that there are two areas erased.

6. Writing the new firmware
The battery needs to be removed and put back on before proceeding.

Selecting the 'Write' tab allows the two firmware files to be selected. I selected my modified 'no logo' version. There's two files to load.

Again, I pressed 'Start' and held in the power button on the phone. This takes about 15-20 minutes, if all goes well.

7. Write back calibration data
After removing and re-adding the battery, I selected the 'Write cal data' tab, and selected the caldata.bin file I made earlier. Pressed 'Start', held down the power button on the phone, and voila. This only takes a few seconds.

8. Turning the phone back on
Again I removed the battery, and plugged it back in. Pressing the power button to turn the phone back on can be a little nerve-racking as the phone seems to take longer to turn on than normal. But it did work.

 

Problems I've had:
- Before perfecting a method to hold the power button in, I slipped off the button a few times. I simply started the flash again, and I have been lucky and have gotten away with it. One time the flash proceeded without me holding the button in, but I've never been able to do it again.
- I have flashed my old G5300 perhaps 10-15 times. It was still working when I stopped using it.
- Once, the flash simply didn't work. After flashing the phone, it refused to turn back on. I reflashed it again, and it was fine. Phew.

Was it worth it? Well, it didn't cost me anything to do this. But I found harldy any java games that worked on the LG, so if you want to play those java games you'll probably be disappointed. This was more of an educational experiment than anything else.

Is there any other way of doing this? Probably. In fact, it might be worth googling 'LGetflash'. This software is meant to be able to change operator text and read/write firmware. It looks very promising, but it kept crashing for me, so I gave up trying to use it. If you have success with it, let me know and I'll update these pages.