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7 Maintenance
7.2 Replacing a Probe
A probe must be replaced if:
• The internal resistances R
ki
-O
2
and R
ki
-CO can no longer be set to values
of 20 Ω (+/- 5 Ω).
To be read at the probe data (Menu 213).
• The probe offset voltages U-O
2
and U-CO in the air assume values above +20 mV or
below -30 mV.
To be read at the probe data (Menus 211 and 212).
• The CO/H
2
electrode does not response
In the MAIN MENU, select for informa-
tion.
In INFORMATION select for measured
values and probe data.
In MEASURED VALUES and Probe Data the
following is available for selection:
Display of the O
2
measured values
(menu 211)
Display of the CO measured values
(menu 212)
Display of the R
ki
internal probe
resistances (menu 213)
Display of the current fuel selection
Reading of O
2
measured values.