Troubleshooting Guide For F61 And/Or F76 - Panasonic SA-AKX34LM-K Service Manual

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.
Symptom
Set cannot ON 1
2
3
4
5
6
1
Set can ON
then F61
2
1 Main Transformer T5701
Set can ON
then F76
2
3
Set can ON 1
working normally
for some time 2
then F76
TH5861
Checking Items
AC Cord 1 AC Cord Faulty, Loose connection
AC Inlet, P5701 2 P5701 solder crack, dry joint .
Fuse, F1 3 Fuse, F1 Open .
Photocoupler 4 PC5702/PC5799 solder crack.
PC5702, PC5799 Dry joint, short circuit, open circuit.
Switching Regulator 5 IC5701 Faulty .
IC, IC5701
Sub Transformer (T5751) 6a T5751 Faulty.
6b Switching Mode Power Supply Control IC (IC5799) faulty.
6c
D5798 faulty.
Speaker Output 1 Faulty speaker unit, Loose connection, Short .
D-AMP circuit 2a D-AMP IC, IC5800 defective.
(Check DC voltage at speaker terminals, 3V and above defective)
2b
DC Voltage ok but no sound, check DC Voltage at Pin 1.
5V ok condition, 2.5V or 0V defective.
2c
2a, 2b ok but no sound, check PWM waveform at Pin 10 and Pin 14 .
If no PWM, 4 resistors defective (R5802, R5803, R5804, R5805).
1a
Short circuit between Pin 11 and Pin 12 .
1b Short circuit between Pin 13 and Pin 14 .
1c Short circuit between Pin 16 and Pin 17 .
Regulator Circuits 2a IC2010 faulty (No +9V output).
2b L2000 Open.
Q2022 faulty (No +5V output).
2c
2d IC2014 faulty (No +3.3V output).
2e IC2011 faulty (No +5V output).
2f L2001 Open.
3
Photocoupler
PC5720 solder crack,
PC5720
Dry joint, short circuit, open circuit.
Rectifier Diode D5801 1a Improper contact between D5801 to Heatsink .
Rectifier Diode D5802 Improper contact between D5802 to Heatsink .
1b Set trigger temperature protection .
Thermistor TH5860,
Possible Fault(s)
28
Remarks
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 9.1.2
Fig. 2. and Fig.3.
Main P.C.B.
Refer to
Section 9.1.1
Fig. 1. SMPS P.C.B.
Refer to Section
9.1.1 Fig. 1. SMPS
P.C.B.