Power is On, but nothing is displayed.
  

Check if the program cartridge is properly inserted.

Should the cartridge is properly insertred, ask for after sales service.
 

15 | 2/2    
5 Product   Display is too dark. 3453
Product   Power is On, but nothing is displayed. 3401
3 Product   Power doesn't work. 3115
2 Product   DTC (Diagnostic Trouble Code) is not erased. 4227
1 After Service   How to use After Sales Service? And how long? [2] 4020
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