General Information; Diagnosis; Diagnosis Method - Pioneer PRO-720HD Service Manual

7. GENERAL INFORMATION

7.1 DIAGNOSIS

7.1.1 DIAGNOSIS METHOD

Various protection circuits are provided for this unit. When these
protection circuits are activated, the power of the unit is shut down
(P.D.: Power Down).
The defective parts can be easily diagnosed by observing the LEDs
inside the following assemblies.
1. POWER SUPPLY Assy
Common to all models
2. DEFLECTION SERVICE Assy
Common to all models
For service assembly
3. CONV. AMP Assy
Common to all models
POWER SUPPLY ASSY
D915
DEFLECTION SERVICE ASSY
CONV. AMP ASSY
SIDE A
LED points
: D915 in the AWV1912
: D321 in the AWV1913
: D321 in the AWV1921
: D923 in the AWZ6649
SIDE A
SIDE A
D321
D923
PRO-720HD, PRO-620HD, PRO-520HD
How to diagnose a failure
The D915 LED of the POWER SUPPLY Assy always lights up
when the power is turned off because of the protection circuits (P.D.).
P.D.
Is only the LED of the
POWER SUPPLY Assy lit?
NO
Which LED is lit, that of the
DEFLECTION SERVICE Assy
or of the CONV. AMP Assy?
DEFLECTION
SERVICE Assy
to P.D (2)
YES
to P.D (1)
CONV. AMP ASSY
to P.D (3)
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