SECTION 7 TROUBLESHOOTING
Symptom Possible Cause Action Ref
Low battery voltage Replace batteries 2.3
Batteries installed wrong Check battery polarity. 2.3
Instrument will not turn on
Meter requires service Return system for service 8
Membrane is fouled or damaged Replace membrane 3.2
Probe anode is fouled or dark Clean anode 5
Probe cathode is fouled Resurface cathode 5
Instrument will not calibrate
System requires service Return system for service 8
Instrument has recorded a shock Remove battery lid, wait 15
seconds for reset, and replace lid.
2
Batteries are low or damaged Remove battery lid, wait 15
seconds for reset, and replace lid.
2
Instrument "locks up"
System requires service Return system for service 8
Cal value is incorrect Recalibrate w/correct value 4.3
Probe not in 100% water
saturated air during Cal
rocedure
Moisten sponge & place in Cal
chamber w/ probe & Recal
4.3
Membrane fouled or damaged Replace membrane 3.2
Probe anode is fouled or dark Clean anode 5
Probe cathode is fouled Resurface cathode 5
Dissolved Oxygen readings
are inaccurate
System requires service
Return system for service 8
LCD displays "LO BAT" Batteries are low or damaged Replace batteries 2.3
Allow sufficient time for
temperature and oxygen
stabilization
4.3
Check for water droplets on
membrane
3.2
Change membrane 3.2
Does not return to calibration
value
Clean probe (see instructions
under Electrode Cleaning)
5
Allow sufficient time for
temperature and oxygen
stabilization
4.4
Allow 60 sec for reading to
stabilize
Change membrane 3.2
Unstable readings
Clean probe (see instructions
under Electrode Cleaning)
5
YSI Incorporated YSI 58 DO Meter 21