Citizservicemanual139
F U N C T I O N  T E S T S
9.7 NTCtem per atu res ens or fu nc ti on alit y
TheresistanceoftheNTCte mperaturesensormustbewit hinadefinedrange,other
wisethetemperatureregulati onwillnotworkproperlyandthecof feemachinewillstay/
gointofailuremode.
AneasywaytocheckthefunctionalityoftheNTCtemperaturesensoristomeasurethe
ohmicresistanceatambient temperature.Withthismeasur ement,mostdefectNTC
temperaturesensorscanbe detected.
Avoidcontamination
ofsensorcontactsur
faceduringhandling.
1) UnplugNTCtemperaturesensorfrom
electroniccontrolboard.
2) RemoveNTCtemperature sensor
fromthermoblock(refertopa ge104
andfollowing).
3) Measuretemperatureofsen sorbody
(donottoucheithertemperat ureor
NTCsensorbyhand).
4) MeasureresistanceofNTC tempera
turesensorbyconnectinga multime
terattheplug.
5) Comparemeasuringvalues withfol
lowingdiagramortable.