SHARP MDC2H
Service Manual

MD-C2H
� Although HF waveform is normal and time indication is normal, no sound is not output.

Check the IC2 pin 48 (EFLG). No Yes Check the IC2 pin 37 and 40. Yes Replace IC2.

Usually, the number of pulses of flawless disc is 100 pulses/sec or less.

TROUBLE-SHOOTING (AMP SECTION)
� Although the power is turned on, the device does not turn on.
Pin 54 on ICF01 changes from L to H. No When the POWER key is pressed, pin 23 of ICD01 will change from 5V to 0V. Yes Yes Power relay RL900 turns on. No Check between pin 54 on ICF01 and Q900. No Check between POWER key and pin 23 on ICD01.

Yes The 5V_SWD line is powered up. (ZD806 cathode) Yes Pin 41 of ICF01 changes from L to H and stays there. Yes Check the supply power to the MD unit. 4.75 < DVCC < 6.75 6.0 < AVCC < 7.0 Yes If the voltage changes from L to H to L, check QV00, QV01, QV02 and QV03 on the SP_PROTECT line on pin 41. No Check the power circuit (F802, Q807, ZD806 etc) Check the serial communication line between ICF01 and ICD01. Make sure that the ON/STANDBY line is H.

Check the power circuit (F803, Q809, ZD805 etc)

Check the peripheral circuits for ICF01 and also the RESET circuit.

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