SONY 910004 Service Manual
MODEL NO.
SUBJECT:
TROUBLESHOOTING GUIDE
START
Service Technical Information
CD PLAYER
Bulletin # 91-01-01
Date: May 11, 2001
CD FUNCTION
SELECT
Yes
IS
CD POWER ON?
Yes
DOES UNIT READ
TOC?
Yes
No
TECH TIP
Use CD test
mode if available
No
CHECK LASER POWER AND
CHECK SUPPLY
FROM MAIN PWB
DOES
LASER
LIGHT?
FOCUS SEARCH
CHECK DISC
No
CHECK APC
CIRCUIT
NOT ALL CD
PLAYERS
ARE CAPABLE OF
READING
CD-R/RW DISCS
DOES DISC PLAY?
Yes
IS
THERE AUDIO
OUTPUT FROM OP-
AMP?
Yes
CD SECTION IS OK
No
No
CHECK TRACKING SERVO
(IF DISC SPINS BACKWARDS, THE UNIT HAS
TRACKING PROBLEMS)
DSP OR
OP-AMP DEFECTIVE
1
DOES
SPINDLE
MOTOR
SPIN?
Yes
CHECK MOTOR,
DRIVE CIRCUIT
No
CONNECTORS
AND
ALL CHECK
GOOD?
Yes
IS
THE 16.9MHZ
CLOCK
CORRECT?
No
X'TAL OR
ASSOCIATED
CHIP CAPS
DEFECTIVE
IS RF
OUTPUT
PRESENT?
Yes
ARE
COIL DRIVE
CIRCUITS
WORKING?
Yes
ARE
THE DRIVE
PULSES COMING
FROM SERVO
IC?
No
No
HOT TIP!
YOU CAN CHECK THE RF AMP BY
TOUCHING THE PICK-UP WIRES WHILE
IN FOCUS SEARCH MODE. THE RF AMP
WILL AMPLIFY NOISE FROM YOUR
FINGER.
HOT TIP!
THE IDLE INPUTS FOR EACH MOTOR/
COIL DRIVE IS AT VREF LEVEL.
MOMENTARILY GROUNDING THE INPUT
WILL CAUSE THE MOTOR OR COIL TO
MOVE IF THE CHIP IS WORKING
ARE
DATA AND
CLOCK PULSES
FROM DSP
PRESENT?
PROPERLY.
No
PULSES FROM CPU
ARE DATA
AND CLOCK
PRESENT?
SOME PICK-UPS HAVE BUFFER
AMPS BUILT IN. IN SUCH CASES,
THE EYE PATTERN CAN BE SEEN
AT THE PICK-UP CONNECTOR.
THE DRIVE IC CONTROLS THE
SLED AND SPINDLE MOTOR AS
WELL AS THE FOCUS AND
TRACKING COILS
CHECK CPU AND
No
INTER-PWB
CONNECTIONS
Yes
SERVO IC OR
SURROUNDING
COMPONENT
MAY BE
DEFECTIVE
THE FOLLOWING APPLIES TO IC # LA9241. REFER TO MANUAL # 09992-325-4N2 TO FIND OUT HOW THIS INFORMATION RELATES TO THE
CIRCUIT YOUR TROUBLESHOOTING.
OPEN CHIP CAP:
SYMPTOM
READS TOC BUT DOESN'T PLAY C16, C41
SKIPS AT OUTER TRACKS C17
DOESN'T READ TOC C18, C19
DOESN'T READ TOC; DISC BARELY SPINS C23
DOESN'T READ TOC; DISC SPINS NORMALLY C31, C101
DOESN'T READ TOC; DISC SPINS VERY FAST C33
SKIPS WHEN READING THROUGH SCRATCHES C39
DOESN'T READ TOC; PU TRAVELS TO OUTER TRACKS
THEN RETURNS TO CENTER & REPEATS PROCESS C13
Yes
DEFECTIVE CAP
CONNECTED
COMPONENT
Yes
DSP OR
DEFECTIVE
2
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