Ricoh C231 Service Manual page 605

4.3 DIP SW, LED, VR, TP, AND FUSE TABLES
4.3.1 TEST POINTS
MPU
No
TP5 GND-a
TP10 +5V
TP11 +5VE
TP23 Ink Detection Pulse
TP25 Standard Pulse
TP28 GND-a
4.3.2 POTENTIOMETERS
MPU
No
VR1 Ink detection adjustment
VR2 Master End Sensor Adjustment
Power Supply Unit
No
RV1 Thermal Head Voltage Adjustment
4.3.3 LED'S
MPU
LED #
LED 1 CPU2 (not use for service)
LED 2 Low Ink Condition
LED 3 CPU1 (not use for service)
LED 4 CPU1 (not use for service)
SM
DIP SW, LED, VR, TP, AND FUSE TABLES
Usage
Usage
Usage
OFF
Sufficient Ink Condition
4-7
ON
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