BeneVision N22/BeneVision N19 Patient Monitor Service Manual                                           4-7
4.7.5 Output Interface Failures 
Fault Symptom  Possible Cause  Countermeasure 
No output for the nurse call  DCDC interface board cable loose  1. Verify the cable connecting the DCDC interface 
board to the main board is properly connected. 
2. Verify the cables and connectors are not 
damaged. 
DCDC interface board damaged  Replace the DCDC interface board. 
Main board failure  Replace the main board. 
USB Device Unusable 
USB enumeration failure  Restart the system. 
Cable defective or improperly 
connected 
1. Verify the cable connecting the USB Hub board to 
the main board is properly connected. 
2. Verify the cables and connectors are not 
damaged. 
USB Hub board failure  Replace the USB Hub board. 
Main board failure  Replace the main board. 
 
 
4.7.6 Power Supply Failures 
Fault Symptom  Possible Cause  Countermeasure 
Battery cannot supply 
power
 
Battery damaged  Replace the battery. 
Cable defective or improperly 
connected 
1. Verify the cable connecting the battery interface 
board to the power module is correctly connected. 
2. Verify the cables and connectors are not 
damaged. 
DCDC interface board damaged  Replace the DCDC interface board. 
Battery cannot be recharged  Battery damaged  Replace the battery and charge fully. If this is 
successful, the original battery is faulty. 
Cable defective or improperly 
connected 
1. Verify the cable connecting the battery interface 
board to the DCDC interface board is correctly 
connected. 
2. Verify the cables and connectors are not 
damaged. 
DCDC interface board damaged  Replace the DCDC interface board. 
No +3.3 V output 
1. Power supply protected 
2. DCDC interface board damaged 
1. Turn off the patient monitor then restart it. 
2. If the problem persists, disconnect the AC mains 
for 5s and reconnect it, and then restart the patient 
monitor. 
3. If the problem persists, replace the DCDC interface 
board.   
No +5.0 V output 
No +12 V output