Turbidity Sensor And Thermistor - GE CDT865SxJ0 Series Technical Service Manual

Diverter Installation Tip: Using rinse aid or water
on the diverter seals will aid diverter installation.

Turbidity Sensor and Thermistor

Operation
The Turbidity Sensor measures the amount of
sensor assembly contains a LED transmitter which
emits light, and a receptor (similar to a photo-
cell) which receives light. The wash water passes
between the transmitter and receptor, then the
control interprets these readings to determine the
soil level and if any prewash or rinse cycles may
be skipped. The cycle design sets parameters to a
maximum cycle length; and the turbidity response
will shorten the overall cycle length if the soil level is
several times during a cycle to monitor soil levels,
energy can be saved by removing unneeded rinses,
thus shortening the overall cycle time.
Thermistor
The Thermistor is located inside the turbidity sensor.
The thermistor monitors water temperature in the
tub. If the thermistor opens or shorts it will cause an
error (see Consumer Error Mode). If it fails in open or
shorted, the control will default to the longest time
algorithm.
To check the thermistor, access the Main Control
(see To Access Main Control Board section under
Main Control Diagnostics). Check resistance on
connector J711, pin 7, YR to pin 8, RN. The sensor
may also be removed and the two outside terminals
may be checked. Use the table above to calculate
the correct resistance reading.
VOLTAGE
.95
1.56
2.25
2.91
3.48
3.91
– 72 –
RESISTANCE TEMPERATURE
20066 50°F
10450 75°F
5824 100°F
3411 125°F
2081 150°F
1330 175°F
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