Resolving Language Selection Issues on the Komatsu PC120-8 Excavator

[MikePhua]

Komatsu PC120-8 Development and Market Reach
The Komatsu PC120-8 is a mid-size hydraulic excavator introduced in the early 2010s as part of Komatsu’s Dash-8 series. Designed for urban construction, utility trenching, and light earthmoving, the PC120-8 features a fuel-efficient Komatsu SAA4D95LE-5 engine, advanced hydraulic controls, and an operator-friendly cab interface. Komatsu, founded in Japan in 1921, has sold millions of machines globally, and the PC120-8 remains popular in Southeast Asia, Latin America, and Africa due to its balance of power and compact footprint.
Many units are exported secondhand from Japan, often arriving with Japanese-language interfaces that pose challenges for non-Japanese-speaking operators. The onboard monitor system includes diagnostic menus, maintenance alerts, and operational settings—all of which are difficult to navigate without proper localization.
Terminology Annotation

• Monitor Panel: The digital display unit inside the cab that shows machine status, error codes, and configuration menus.
  
• F-Buttons: Function keys (F1–F6) located below the monitor, used to navigate menus and confirm selections.
  
• Quick Press vs. Press-and-Hold: A dual-function input system where short taps and long presses trigger different menu behaviors.
  

Symptoms of Language Selection Failure
Operators attempting to change the language from Japanese to English often report that:

• The language menu is accessible but unresponsive
  
• F3 and F4 buttons do not scroll through options
  
• No arrows appear on the screen to indicate selection movement
  
• Only the F5 button works, returning to the previous menu
  

This behavior suggests that the interface is locked in a passive state or that the correct input sequence has not been initiated.
Recommended Input Sequence and Troubleshooting
To successfully change the language:

• Access the main settings menu using the monitor panel
  
• Use a press-and-hold action on the F6 button to activate the selection mode
  
• Once arrows appear, use F3 and F4 to scroll through available languages
  
• Confirm the selection with a short press of F6
  
• Use F5 to exit and save changes
  

If the arrows do not appear, it indicates that the menu is still in view-only mode. The system requires a deliberate press-and-hold to unlock interactive navigation. This dual-mode input system is common in Komatsu’s Dash-8 series and is designed to prevent accidental changes during operation.
Field Anecdotes and Practical Advice
In Thailand, an operator received a secondhand PC120-8 from Japan and struggled with the Japanese interface. After experimenting with the F-buttons, he discovered that holding F6 for three seconds activated the scroll arrows. He was then able to switch to English and access maintenance logs.
In Indonesia, a technician used a poorly filmed video tutorial in his native language to guide a colleague through the process. Despite the language barrier, the visual cues helped identify the correct button sequence.
In Vietnam, a fleet manager noted that some imported units had firmware versions that locked language settings. In such cases, a dealer-installed software update was required to unlock the menu.
Preventive Measures and Long-Term Solutions
To avoid future language issues:

• Request language configuration during import or purchase
  
• Verify monitor firmware version and update if necessary
  
• Label F-buttons with translated functions for non-native operators
  
• Keep a printed guide of menu navigation steps in the cab
  
• Train operators on dual-function input behavior
  

For fleets with mixed-language machines, consider standardizing monitor settings during commissioning to reduce confusion and improve safety.
Industry Trends and Localization Improvements
Komatsu has increasingly focused on multilingual support in newer models. The Dash-10 and Dash-11 series feature touchscreen monitors with intuitive icons and expanded language libraries. Some units now auto-detect region settings based on GPS or dealer configuration.
In response to global resale markets, Komatsu has also begun offering downloadable manuals and interface guides in multiple languages. These resources help bridge the gap for operators working with secondhand imports.
Conclusion
Changing the language on a Komatsu PC120-8 excavator requires understanding the monitor’s dual-mode input system. By using a press-and-hold on the F6 button, operators can unlock the scroll function and select their preferred language. With proper training and awareness, this minor but critical adjustment can dramatically improve usability and reduce operational errors. As Komatsu continues to expand its global footprint, multilingual support will remain a key factor in machine accessibility and operator satisfaction.