Am I able to install English onto my Panasonic Strada CN HS400 Navigation system, because it's in Japanese so I can't use it

Some Strada models are made for the Japanese domestic market and only come in Japanese.

Use the Google Translate App Camera trick.

https://www.google.com/search?q=change+the+language+of+my+panasonic+strada+CN-S310D+FROM+JAPAN+TO+ENGLISH

No it cant, i had the same thing and have been down that path. It requires navigation DVD's of UK maps, for mine which are proprietary to the Japanese gps system and they do not exist in other languages.

https://www.manualslib.com/manual/360975/Panasonic-Strada-Cn-Nvd905u.html
https://www.manualslib.com/manual/1392340/Panasonic-Strada-Cn-Nvd905u.html
Visit these sites. You can download user manual, as well as service manual of the set, from these sites. If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
https://elektrotricks.blogspot.com/
faults & possible causes to LCD screen are given with illustrations. You can get an idea about the fault to an extent. Search the site by type in the brand name and model of your set, in its search bar at the right side column, and press enter.

You don't say what is wrong, so it is difficult to troubleshoot. Here are links though. Or take it to the nearest Panasonic service centre.

https://www.google.com/search?q=panasonic+strada+cn-hds945td+troubleshoot

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Everyone posts in English and you post in Espagnol!

Hello network, excuse me, please have user manual for Panasonic strada dvd car navi station. CN-DS100D

It looks like this model is made solely for the Japanese market. Manuals only in Japanese.

https://www.google.com/search?safe=off&rlz=1C1QJDB_enCA643CA644&sxsrf=ALeKk019HdUMzHgxceqLdk2uagR_My3YUQ%3A1612891715583&ei=Q8YiYOPnItHKswWinoWADg&q=Panasonic+strada+dvd+CN-DS100D

English to Espagnol

https://translate.google.ca/?hl=en&tab=TT&sl=auto&tl=en&text=Hola%20red%20disculpen%20por%20favor%20tendran%20manual%20de%20usuario%20de%20Panasonic%20strada%20dvd%20car%20navi%20station.%20CN-DS100D&op=translate

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Yeah! This is possible. If you do not understand the Japanese language and using Gps then it is very hard to drive for you. Here are some simple steps for change Language.

Step 1:
Turn off your car and turn it on looking for a button that says "English." Some cars will have an option to change the language as soon as the car is turned on.
Step 2:
Look for a button around the touch screen marked "Language" or "LANG." Press this button and then press the button for "English" on the touch screen.
Step 3:
Check to see if your navigation system is a GPS system or a DVD system. If the system is a DVD system, you may have to call the company and purchase an English language disc. These can cost upwards of $150.
Step 4:
Take your car into a dealership that services your model of car. Many times they will be able to reprogram the computer for free, though some systems require more work and may be costly to change.
If you want to update your downloaded Gps Device then you should feel free to browse our website or click on the Given link below and reach your destination very easily hassle free.

https://www.gpsupdatesupport.com

Panasonic Strada CN NVD905U Operating Instructions Manual https://www.youtube.com/watch?v=siY-nxirm-k

O believe that is a Japanese spec unit and doesn't support english, the navigation system won't work outside Japan either.

How to change language to English on Panasonic strada CN-L880LED