Hi Enes. Welcome to justanswer.
Can you access the Menu option?
Do you see an icon of a gear in the Menu? (Settings)
Select it and now go to each option that you see. There will be an option of Language setting. Since it is in Japanese, select each and see if there is an option to select language. You will see English as one of the option in the drop down list if there is any.
I am sorry then I won't be able to help you as this is the only way
No it will say English as English only. Do you see any sign of More settings under settings?
You can factory reset it and then when you will set it again, you will be asked to set the language again.
Can you see a RESET button on your device, just to the left of the tray where you put in CD.
Check this image. Is there any button like this on your device
Then there is no button to reset the device without going to Settings.
You willl need to remove the battery to reset the device but this will void the warranty if present
Is it still under warranty?
No that will not fix it
Yes that's the only way. Did you accidentally changed the language?
Or you can use google translate to interpret the Japanese menu.
Actually this model was released only in Japan.
I would advise you to better get this replaced as the English maps will not be compatible with this device.
You can try resetting it by getting the battery removed from any repair technician and selecting the language.
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