Thread: 3590 LTM keyboard language supported ?

CN & TW 3590, despite having the same model number as US/EU 3590, are totally different devices to your 3590. They are Android OS and yours is proprietary Garmin OS.

The closest to your US 3590 is the Asian 3560. SG, TW & CN versions are cross-flashable between each other because they have the same PCB P/N 105-01887-02 and share HWID 1521. The US/EU device is PCB P/N 105001887-10 and HWID 1258 and it is not flashable to the Asian fws using original fw. You can try using the US boot.bin and keeping HWID 1258 but will get 'System Software Missing' or similar message and incomplete boot. Don't bother trying it.

The CN fw is needed to handle the official 'shifted' maps. There are some tricks to using Chinese maps with US/EU fw devices though such as using the 'Venus' non-shift corrected maps in English to search. I understand that it's somehow possible to have both English/Pinyin & CN maps loaded with only one enabled and have some features displayed in Chinese using a Pinyin map. syzygy is the guy to explain how to do that. Have a look at [Only registered and activated users can see links. ] and maybe post there for more info on that, but i don't know if there is an EN or Pinyin version available for the latest version yet.