SONY DVPNS755V
Service Manual

6-11-3. Drive Auto Adjustment stops due to error. The ARP & SERVO (IC301) analog circuit of MB-105 board is defective or RF-Amp (IC201) or M-Driver (IC202) peripheral circuit is defective or optical pickup block is defective or flat cable connection is defective 6-11-4. The product itself is defective. � If MB-105 does not have any problem, The board other than MB-105 board is defective or connection is defective or optical pickup block is defective or mechanism deck is defective 1. Power LED does not light in Red when the AC power is turned on. Check the EVER �13V (pin-3), EVER+3.3V (pin-qa), +11V (AUDIO) (pin-qd) voltage of the power supply block CN201. If voltage is abnormal. t The power supply block is defective. 2. Power LED does not light in green after transmitting the POWER on command. It remains lighting in red (in the STANDBY mode). 2-1. Check the EVER -13V (pin-3), EVER+3.3V (pin-qa), +11V (AUDIO) (pin-qd) voltage at CN201 of the power supply block/ If voltage is abnormal. t The power supply block is defective. 2-2. Check if the fuse on the IF board has blown of not. If the fuse has blown t Replace the fuse. 2-3. Check the P-CONT (pin-2) at CN401 of the IF-94 board when the POWER button is pressed. If it remains at �L�, t The signal line has the defective soldering or it is shortcircuited with other signal lines or capacitor or resistor is defective or IFCON is defective or connection between the power supply block and the IF-94 board is defective, or connector installation is defective, or the power supply block is defective. 2-4. Check if the button is kept depressed in the IFCON self mode. If the button is kept depressed. t The front panel is defective, or IF-94 board is defective. 2-5. Check PONCHK (pin-e;) of IFCON (IC404) on the IF94 board. If it is 0.5 V or more. t The power supply is defective, or IF94 board is defective. 3. Power LED becomes red (STANDBY mode) in at once through Power LED lights in Green once when the POWER button is pressed. 3-1. Check CN201 voltage of the power supply block when the LED lights in green. If voltage is abnormal. t The power supply block is defective, or the IF-94 board is defective, or MB-105 is defective

3-2. Check XFRRST (pin-9) at CN101 on the MB-105 board. If it is fixed to �L�. t The signal line has defective soldering, or is short-circuited with other signal lines, or parts are defective. 3-3. Check IFBSY (pin-0), XIFCS (pin-qa), SI0 (pin-qs), SO0 (pin-qd) and SC0 (pin-qf) at CN101 If they are fixed to �H� or �L�. t The signal line has defective soldering, or is short-circuited with other signal line, or parts are defective, or SYSCON (IC104) is defective If they change between �L/H�. Connector installation is defective, or the IF-94 board is defective, or SYSCON (IC104) is defective. If they stay in the center voltage. Poor connection of flexible wiring board such as it is inserted in an angle diagonally, or defective soldering, or is short-circuited with other signal line. 3-4. Check PONCHK (pin-e;) of IFCON (IC404) on the IF-94 board. If rise-up time from 0.5 V to 1.5 V or more takes longer time, or it does not exceed 1.5 V or more. t The IF board is defective. 4. The LED lights in green but the FL display does not light when the POWER button is pressed. Connection between the power supply block and the IF-94 board is defective, or connector installation is defective, or the IF-94 board is defective. 5. Both picture and audio are not output. Connection between the power supply block and the IF-94 board is defective, or connection between the IF-94 board and the AV-64 board is defective, or connection between the AV64 board and the MB-105 board is defective, or connector installation is defective, or AV-64 board is defective. 6. Picture is not normal. (Block noise or others appear.) The MB-105 board AVD (IC403) or SDRAM (IC404, IC405) is defective, or ARP & SERVO (IC301) is defective.

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