Skip to main content
Thermo Fisher Scientific

HT Can’t Start,Gun dialog shows “External interlock”

Issue

HT cannot start,Gun dialog shows “External interlock”

Environment

Krios G3i

Resolution

These are possible resolutions for the issue:

  • Replace VGIB

Cause

These are possible causes for the issue:

  • Defected VGIB cause external vacuum interlock

Details

  1. FEG is normal, but HT cannot start.
  2. Almost all HT TAD tests failed on “HT on conditions” or “check HT and AUX are switched off”
  3. Gun dialog shows “External interlock”
  4. PILZ position was verified
  5. K1 on IETM is the vacuum interlock relay, follow this path and found that VCBT is working properly, but VGIB is not generating output voltage back to IETM  
  6. Replace VGIB and the issue was fixed

clipboard_efb2fa1b4e74b0945b9b13e4c84a1a8d2.png

clipboard_ea1c5b2ebf4389f79c9ac88544c093ad8.png

 

 

  • Was this article helpful?