Skip to main content

TQD not communicating with MassLynx after a crash vent - WKB14095

Article number: 14095


  • "Instrument not present" message
  • Roughing pump not responding to pump command


  • TQD
  • SQD
  • 3100
  • MassLynx 4.1


Mass spectrometer powered-on before instruments


  1. Shut down MassLynx and the MS console.
  2. Navigate to C:/ Program Files X86 / Waters Instruments / Waters DHCP Server Configuration.
  3. Remove all components in the list (you can remove only one component at a time).
  4. Power-off the LC, the mass spectrometer, and the computer.
  5. Power-up the computer and log in to Windows.
  6. Follow step 2 and leave the DHCP Server Configuration window open.
  7. Power-on the LC stack, starting with the component that contains the Ethernet hub.
  8. Monitor the DHCP Server Configuration window to ensure that all LC components populate completely.
  9. Power-on the mass spectrometer and monitor the DHCP Server Configuration window until the mass spectrometer populates completely.
  10. Open MassLynx.
  11. Open tune page, select vacuum, and pump.
  12. The roughing pump will take approximately five seconds to kick on.
  13. Navigate to the diagnostics tab of the tune page and monitor turbo speeds. Once they reach 80%, place the mass spectrometer in Operate mode and turn on the API gas. 
  14. If the mass spectrometer was powered-off for an extended period of time, it is best to wait at least four hours for the system to reach optimal vacuum levels. 


Never power-off the mass spectrometer when it is under vacuum. The system should first be vented through the tune page. 

Not able to find a solution? Click here to request help.