Check Points For Each Error - JVC XV-S300BK Service Manual

3.7 Check points for each error

3.7.1 Spindle start error
(1) Defective spindle motor
• Are there several ohms resistance between each pin of CN201 "5-6","6-7","5-7"?
(The power supply is turned off and measured.)
• Is the sign wave of about 100mVp-p in the voltage had from each terminal?
[ CN201"9"(H1-),"10"(H1+),"11"(H2-),"12"(H2+),"13"(H3-),"14"(H3+) ]
(2) Defective spindle motor driver (IC251)
• Has motor drive voltage of a sine wave or a rectangular wave gone out to each terminal(SM1~3)
of CN201"5,6,7" and IC251"2,4,7"?
• Is FG pulse output from the terminal of IC251"24"(FG) according to the rotation of the motor?
• Is it "L(about 0.9V)" while terminal of IC251"15"(VH) is rotating the motor?
(3) Has the control signal come from servo IC or the microcomputer?
• Is it "L" while the terminal of IC251"18"(SBRK) is operating?
Is it "H" while the terminal of IC251"23"(/SPMUTE) is operating?
• Is the control signal input to the terminal of IC251"22"(EC)?
(changes from VHALF voltage while the motor is working.)
• Is the VHALF voltage input to the terminal of IC251"21"(ECR)?
(4) Is the FG signal input to the servo IC?
• Is FG pulse input to the terminal of IC301"69"(FG) according to the rotation of the motor?
3.7.2 Disc Detection, Distinction error (no disc, no RFENV)
• Laser is defective.
• Front End Processor is defective (IC101).
• APC circuit is defective. --- Q101,Q102.
• Pattern is defective. --- Lines for CN101 - All patterns which relate to pick-up and patterns between IC101
• IC101 --- For signal from IC101 to IC301, is signal output from IC101 "20" (ASOUT) and
IC101 "41"(RFENV) and IC101 "22" (FEOUT)?
XV-S300BK/XV-S332SL/XV-S402SL/XV-S403SG
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