Quote:
Originally Posted by ag4ever
If you do the software update, will it loose that data if the power is cut from the radio for an extended period of time?
I know I forced a software reload in my camry by pulling the radio fuse for 30 seconds when I switched from my 6.1 disk to the 5.1/6.1 hybrid disk.
|
Yes, it might be possible to lose the firmware during an extended power loss.
Firmware normally stays resident in the EEPROM chips unless/until the chips are damaged or it is overwritten by new code, even when the power is out which is why it is called "firmware" instead of "software". When you first turn on the vehicle the NAV unit checks the disc for a file which contains the version number of the firmware. If the disc has a newer version than the existing firmware version number then it automatically upgrades the firmware for you.
When you want to downgrade firmware you have to remove power to the NAV unit for a while to clear out the existing version number which will force the NAV to upgrade from the disc regardless of what version it contains.
It is possible that the firmware will still be retained during a power outage, but since the NAV will always attempt to reload from the disc after a power outage then the only way to test this would be to insert a disc which only contains map data (no firmware at all) and see if the NAV still works when power is restored. My assumption is that you could just remove the Loading.KWI file for the test since I think this file is only used on a reinstall but I am not sure.
If anyone tests this then please let us know.