Image Density Sensor; Fusing Thermistor Abnormal - Ricoh FT4430 Service Manual

16 April '88

32 IMAGE DENSITY SENSOR

- Possible Causes -
+ PTL not set.
+ Dirty ID sensor.
+ ID sensor circuit failure.
- Action -
Clean the ID sensor and reset the PTL unit.
Adjust Vsg using VR201 on the main board. Vsg should be 4.0 * 0.2 volts.
If the problem still exists, check the input at CN203-5. Is it less than 1.0 volt?
I
Y N
I
Replace the PTL unit.
Replace the main board.

53 FUSING THERMISTOR ABNORMAL

- Possible Causes -
Thermistor failure. (The input at CN206-BI is less than 0.5 V.)
Action -
-
+
the fusing thermistor.
Replace
11-24