Pioneer PRO-720HD Service Manual page 26

PRO-720HD, PRO-620HD, PRO-520HD
1. P.D. (1)
Failure in the POWER SUPPLY Assy and the AUDIO Assy.
There are four main possibilities:
1. Abnormality in the regulator of the heater
2. Blown fuse(s) in secondary
3. Abnormality in RELAY (RY102)
4. Abnormality in AUDIO OUTPUT
Status Causes
D223 Abnormality in the regulator for
ANODE Hi the heater
D207
Blown fuse(s)
ANODE Hi
D911
Abnormality in RELAY
ANODE Hi
D203
Abnormality in AUDIO OUTPUT
ANODE Hi
Note: The anode of the diode is high only for a short time after the power is turned on until the protection circuits are activated (P.D.) The
LEDs are lit by the HOLD circuit.
In a case when the power cannot be on with no LED lit, check the following:
1. Check if the FU101 fuse in the POWER SUPPLY Assy is blown.
2. Disconnect and check connector E1 (CN201) to see whether STB 5 V is supplied.
If STB 5 V is supplied, replace the SIGNAL Assy. If STB 5 V is NOT supplied, replace the POWER SUPPLY Assy.
3. Disconnect and check connector E1 (CN201) to see whether AC CLK is supplied.
If AC CLK is supplied, replace the SIGNAL Assy. If AC CLK is NOT supplied, replace the POWER SUPPLY Assy.
2. P.D. (2)
Failure in the DEFLECTION SERVICE Assy.
There are four main possibilities:
1. H. deflection overload detection (1)
2. H. deflection stopping detection
3. H. deflection overload detection (2)
4. X-ray protection
Status Causes
D312
Overload detection 1
ANODE Hi
D309
Stopping H. deflection
ANODE Hi
D615
Overload detection 2
ANODE Hi
D621
X-ray protection
ANODE Hi
208
Check Items
The voltage of HT- at TP205 is NOT approx. 19 V, and
that of the HT+ at TP204 is NOT approx. 26 V.
The voltage HT+ (approx. 26 V) at TP204 is NOT
supplied.
The voltage (approx. 35 V) at TP203 is NOT supplied.
The voltage (approx. 11 V) at TP209 is NOT supplied.
The RELAY signal is NOT high (ON) at TP904.
P.D. even if the RELAY signal is high (ON) at TP904.
The SP line (CN5611) is disconnected.
The voltage at the negative electrode of the C5616 and
C5617 is 5.2 V or more.
Check Items
Is the connector of the deflection yoke plugged in?
No H. OSC signal at TP304 (F=31.5 kHz, Duty 50%)
No DH. BLK signal at TP305
About one minute after the power is turned off, disconnect
the K4 connector and turn on the power. Then the power is
not turned off (no P.D.).
No change in the ABL voltage (no DC change) at Pin 12 of
the CN305 when a 100%-white signal is repeatedly
connected and disconnected
Probable Defective Parts
Q201, R202, D210, D209
CONV. AMP Assy and
DEFLECTION SERVICE Assy
AUDIO Assy
VIDEO Assy
SIGNAL Assy
Q904, Q905 RY102, R102
Connect the SP line.
C5616, C5617 (VIDEO Assy)
Probable Defective Parts
Q309, Q324 (short-circuited between
C and E)
Plug in the connector.
IC301, Q309
Q309
Q612, Q613 (short-circuited between
C and E)
IC5101, IC5151 and IC5201 in the
CRT DRIVE Assy
D2224 (short-circuited)of the SUB
VIDEO Assy
T601 (FBT) rare short