Ricoh A151 Field Service Manual page 230

Check that CN103 on the main board is correctly connected.
Correct Open
Connect CN103.
Is there 0 volts at CN103-8 on the main board when the lens H.P. sensor is
deactuaed?
No Yes
Replace the main board.
Check whether the dc harness (signal line) for the sensor is defective.
No Defective
Replace the dc harness.
Replace the lens H.P. sensor.
A151/A152 6-36 FSM