Ricoh A151 Field Service Manual page 245

No
Is Vsg less than 2.5 volts when checking TP110 on the main board with SP
54?
No Yes
Readjust Vsg to 4.0 ± 0.2 volts.
Check whether the ID sensor has a short.
No short Short
Replace the ID sensor.
Replace the main board.
FSM 6-51 A151/A152