8-5 
Message 
Alarm 
Priority 
Cause  Solution 
calibration.  
4. Replace the VCM board and perform 
calibration.  
Calibrate Flow 
Sensor and Insp 
Valve 
Low 
1. The calibration table is not 
found in the EEPROM. 
2. The checksum of 
Calibration table does not 
match. 
Perform maintenance calibration. Refer 
to chapters related to the flow sensor 
calibration.  
Calibrate 
Pressure Sensor 
and PEEP Valve 
Low 
1. The calibration table is not 
found in the EEPROM. 
2. The checksum of 
Calibration table does not 
match.. 
Perform maintenance calibration. Refer 
to chapters related to the pressure 
sensor calibration.   
Calibrate O2 
Sensor 
Low 
1. The calibration table is not 
found in the EEPROM. 
2. The checksum of 
Calibration table does not 
match. 
3. The AD difference between 
the 100% and 21% O2 
concentrations in the O2 
sensor table is smaller than 
79AD.  
1. Calibrate the O2 sensor. 
2. If the problem persists, replace the 
O2 sensor.   
Ventilator 
Initialization 
Error 
Ventilator 
Initialization: 
Time out 
High 
After the machine is powered 
on, the CPU board cannot send 
the control parameter settings 
to the VCM board. 
1. Restart the anaesthesia machine. 
2. Reconnect or replace the 
communication line between the CPU 
board and the VCM board.   
3. If the problem persists, replace the 
VCM board.   
4. If the problem persists, replace the 
CPU board.   
Drive Gas 
Pressure Low 
High  The drive gas pressure is low. 
1. Check whether the gas supply is 
normal.  
2. Short circuit the pressure switch. 
The alarm should disappear. If the 
alarm does not disappear, the pressure 
switch fails. Replace the pressure 
switch. If the pressure switch does not 
fail, check the connection between the 
pressure switch and the VCM board.   
3. If both of the preceding items are