Panasonic AG520VDH - COMB. DVD/VCR/TV, Service Manual

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AG-520VDH
TROUBLESHOOTING HINTS
How to confirm whether DVD circuit or other circuits is defective.
1) Confirm DVD operation and VCR operation
OK
OK
Playback the test DVD disc.
The Message "PLEASE CHECK THE DISC, AND
FOR STAINS OR SCRATCHES ON DISC" appears.
Confirm communication between DVD Main C.B.A.
and Main C.B.A. by referring to "Communication Timing
Chart 2."
Confirm that the OPEN/CLOSE TRAY works correctly.
Check points:
Pin 48 of IC6001 on the Main C.B.A.
(DVD_POWER_ON(H))
300 ms
1. Output Signal from DVD Main C.B.A.
(TP8006 (DVD_SCK) on the DVD Main C.B.A.)
Troubleshooting Hints
DVD Main C.B.A. is defective. NG
Repair the DVD Main C.B.A.
IC8001 or the circuit around it is defective.
DVD Mechanism Unit or IC8801 is defective.
DVD Mechanism Unit or IC8801 or IC8001 is defective.
NG
Repair it by referring to the "Tray Operation Problem. "
DVD Mechanism Unit is defective.
Replace the DVD Mechanism Unit.
Repair it referring to "Spindle Motor Operation Problem,"
and " Traverse Operation Problem," "Cause: Pickup
Problem."
If there is problem with audio
or picture, even though it plays
back.
DVD Main C.B.A. is defective.
Repair DVD Main C.B.A.
1. Playback a VHS tape.
DVD circuit is defective.
Main C.B.A. is defective. Both NG
No PB VCR only
No PB DVD only
How to confirm whether DVD Mechanism Unit or DVD Main C.B.A. is defective.
NOTE:
Host communication may not occur correctly between IC6001 on the Main C.B.A. and IC8001 on the DVD Main C.B.A.
when there is a problem on the DVD Main C.B.A.
(Serial Data Communication failure between IC6001 and IC8001 within 30sec. IC6001 will switch automatically to VCR.)
(Check the VCR mode indicator and DVD mode indicator on the Front Light-up Indicators.)
Check the voltage during the 30 seconds during which the unit remains in DVD mode.
First, confirm that the Main C.B.A. is O.K. other than DVD
Mechanism Unit and DVD Main C.B.A. by referring to
"Communication Timing Chart 1," and "Communication
Timing Chart 2."
Check points:
1. All Power Supply Voltages for DVD circuit
(TP8011 (SW_+3.3V_DVD), TP8523 (SW_+5V_DVD),
TP8823 (M_VM_+6V / 5V) on the DVD
Main C.B.A.)
2. Output Signal from DVD Main C.B.A.(TP8009 (D_RDY)),
Output Signal from Main C.B.A.(TP8005 (H_RDY))
(TP8009 (D_RDY), TP8005 (H_RDY) on the DVD Main C.B.A.)
2. Playback a DVD disc. Repair the Main C.B.A.
Main C.B.A. is defective. NG
Repair the Main C.B.A.
Main C.B.A. is defective.
Repair the Main C.B.A.
Perform troubleshooting referring to "How to confirm whether DVD Mechanism Unit or DVD Main C.B.A. is defective."
Troubleshooting Hints of DVD Mechanism Unit
Tray Operation Problem
OK
IC8801 on the DVD Main C.B.A. is defective.
Replace IC8801 on the DVD Main C.B.A. OK
Communication Timing Chart 1
Communication Timing Chart 2
TP8010 on the DVD Main C.B.A.
(DVD_RESET(L))
TP8005 on the DVD Main C.B.A.
(H_RDY (VCR DVD)
1 s
DVD SERIAL START
DVD SERIAL START
21 ms
1 ms
MAX 3.2 ms
16151413121110 9 8 7 6 5 4 3 2 1
TP8009 on the DVD Main C.B.A.
(D_RDY (DVD VCR)
TP8006 on the DVD Main C.B.A.
(DVD_SCK (DVD VCR)
OK
Check the voltage at TP8958 on the DVD Sub C.B.A.
During Stop: 1.65V
During Loading: 1.3V
During Unloading: 1.9V
Check the voltage at TP8806 (TRAYIN) on the DVD
Main C.B.A.
During Stop: 2.5V
During Loading: 1.3V
During Unloading: 3.8V
NG
IC8001 on the DVD Main C.B.A. is defective.
Replace IC8001 on the DVD Main C.B.A.
NG
AG-520VDH
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