Panasonic SA-AKX14, Service Manual

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9.2. Troubleshooting Guide for F61 and/or F76
This section illustrates the checking procedures when upon detecting the error of “F61” and/or “F76” after power up of the unit. It is
for purpose of troubleshooting and checking in SMPS & Main P.C.B.
5 S witching Regulator 5 IC5701 Faulty.
6 V oltage Regulator
Transistor (Q2022 )
6 Q2022 Faulty.
Set can ON 1 S peaker Output 1 Faulty speaker unit, Loose connection, Short.
then F6 1
2 D -AMP circuit D-AMP IC, IC5902 defective.
(Check DC voltage at speaker terminals, 3V and above defective)
DC Voltage ok but no sound, check DC Voltage at Pin 1.
2a, 2b ok but no sound, check PWM waveform at Pin 10 and Pin 14 .
If no PWM, 4 resistors defective (R5905, R5926, R5936, R5928).
Set can ON
1 Main Transformer T5701 Short circuit between Pin 14 and Pin 15.
then F7 6
1b Short circuit between Pin 15 and Pin 16.
1c Short circuit between Pin 16 and Pin 17.
2 DC-DC Circuit 2a
2b
3
(i) +5V Switching Voltage Regulator (IC2011).
(ii) +3.3V Voltage Regulator (IC2009).
(iii) +9V Voltage Regulator Circuit (Q2021, D2004).
(iv) CD +7.5V Regulator Circuit (Q2000, Q2022, D2017).
3 P hotocoupler
PC5720 solder crack,
PC5720
Dry joint, short circuit, open circuit.
1 R ecti•er Diode D580 Improper contact between D5801 to Heatsink.
Recti•er Diode D5802 Improper contact between D5802 to Heatsink.
2 T hermistor TH5860 1b Set trigger temperature protection.
Set can ON
working normally
for some time
then F7 6
Symptom Remarks
Set cannot ON 1 A C Cord 1 AC Cord Faulty, Loose connection.
2
3
F use, F1 3 Fuse, F1 Open.
4 P hotocoupler 4 PC5702/PC5799 solder crack.
PC5702, PC5799 Dry joint, short circuit, open circuit.
Check cable wire connection between cable wire CN2000.
(At Main P.C.B) & connector CN5802 (At SMPS P.C.B)
Possible Fault(s) Checking Items
AC Inlet, P5701 P5701 solder crack, dry joint.
IC, IC5701
2
1a
Refer to
Section 9.1.1
Fig. 1. SMPS
P.C.B.
Refer to
Section 9.1.2
Fig. 2. Main P.C.B.
Refer to
Section 9.1.1
Fig. 1. SMPS P.C.B.
Refer to Section
9.2.1 Fig. 1. SMPS
P.C.B.
Refer to
Section 9.1.2
Fig. 2. Main P.C.B.
Refer to
Section 9.1.1
Fig. 1. SMPS
P.C.B.
2b
2a
5V ok condition, 2.5V or 0V defective.
2c
1a
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