What to do if the yellow and green LED indicators are blinking with 4 short audible beeps on my Drucker Diagnostics Laboratory Equipment?
- LLarry LopezSep 2, 2025
This indicates the internal tachometer hasn't sensed a speed, the sensed speed is out of range, or the wrong rotor is installed. Verify the rotor being used is programmed correctly in the settings and reprogram the correct rotor selection if needed.





