Nellcor OxiMax N-550, Service Manual

Page: 57 / 138

Troubleshooting
N-550 47
Display/Alarms
Table 8 lists symptoms of problems relating to non-functioning displays and
audible tones or alarms and recommended actions. If the action requires
replacement of a PCB or module, refer to
Disassembly Guide on page 55.
Table 8: Display/Alarms Problems
Symptom Recommended Action
Display values are
missing or erratic. Try another sensor or relocate the sensor.
Replace the Sensor Extension Cable.
Replace the sensor.
Replace the Front Panel PCB. See Front Case
Disassembly on page 58.
Not all display segments
light during POST. Check the connection between the Front Panel PCB
and the Main PCB.
Replace the Front Panel PCB. See Front Case
Disassembly on page 58.
All Front Panel LED
indicators do not light
during POST Check the connection between the Front Panel PCB
and the Main PCB.
Replace the front case. See Front Case Disassembly
on page 58.
Alarm sounds for no
apparent reason. Moisture or spilled liquid can cause an alarm to sound.
Allow the N-550 to dry thoroughly before use.
Replace the Front Panel PCB as described in Front
Case Disassembly on page 58.
Display is flashing, but
there is no alarm. Verify that alarm silence has not been activated. See
Menu Item 12 (Silence Alarms) on page 40.
Check speaker connection to Front Panel PCB. Refer
to
Front Case Disassembly on page 58.
Replace the speaker. Refer to Front Case Disassembly
on page 58.
Replace the Front Panel PCB. Refer to Front Case
Disassembly on page 58.