!!
critical Omron
Error Code / appears or the monitor is turned off unexpectedly during a measurement.
Batteries are depleted; monitor shut down unexpectedly.
? What Causes This
Battery depletion during operation
✓ How to Fix It
1. Replace all 4 batteries with new ones immediately as per instructions in section 2.
Source: page 39 of the official manual
From the manual
This error code appears in:
Omron BP7250 Blood Pressure Monitor