Panasonic SA-VK680PU Service Manual page 41

7.1.2. Troubleshooting Guide
Symptom
FL display blinking with
abnormal segment when
power ON the set or "F61"
First Power ON Display
immediate show "F61".
Power ON for a while then
only trigger "F61".
(Symptom always happen)
Power ON for a while and
then trigger "F76"
Checking Items
Check the soldering of the SMPS
P. C.B.
Is there any solder crack at area
(Q5860,Q5861, Q5862,TH5860)
Check all the supply line
Is there any solderability at area
of feedback circuit
Check feedback circuit (IC5801,
Q5802, D5806, PC5720, D5725)
Check Speaker output by using
multi-meter,
If there is a DC Voltage around
30V
Check Output IC (Pin 10 &
14) which have DC Voltage at
Speaker output short to
Vdd/Vss
If shorted that means D-Amp
damage already.
Check the fan connection &
feedback loop:
If the fan not proper connected,
"F61" will trigger when the
volume increase.
If the fan is not working, check
for fan circuit.
Check the soldering of the SMPS
P. C.B.
Is there any solder crack at area
(Q5860,Q5861, Q5862,TH5860)
C heck all the supply line
+18V at ZJ2701 (Pin 8 & 9)
Check all supply voltages as
follows:
Step 1: Check for supply voltages
from SMPS P. C.B to Main
P. C.B at pin 2,5,8,9 of CN5802.
If there are supply voltages,
proceed to Step 2.
If no voltages detected, check wire
connection and circuitry connection
from SMPS P. C.B.
Step 2: Check if there is supply
voltages for Vp, FL1 & FL2
CN2807
If there is supply voltages of
+2.7V at CN2801, Pin 19 & 17
+5V at CN2801, Pin 26
+5V at CN2807, Pin 5
If t here is supply voltages of
9V at CN6001
Tou ch-up the solder crack area/
Change the defective parts.
Q5860,Q5861,Q5862,TH5860
(Tem perature Detect)
30V QR5801 & QR5802 ( 30V
Detect)
Tou ch-up the necessary areas
IC5801,
PC5720, D5725
Change the defective parts.
D-AMP IC:
IC5000/IC5200
P/N = C1BA00000492
For Configuration
Refer to Figure 5
Re-connect the Fan to CN2810
Fan circuit: Q2942, Q2943,
Q2948 & Q2949
Touch-up the solder crack area/
Change the defective parts.
Q5860,Q5861,Q5862,TH5860
(Tem perature Detect)
QR5801 & QR5802 ( 30V
30V
Detect)
Feedback Circuit: IC5801, Q5802
PC5720, D5725, D5806
Check and change the possible
defective parts.
FP2901 (Fuse Protector),
T2900, D2901
IC4000 (Switching Regulator IC)
& related regulator circuit
components
41
Repair Items
Q5802, D5806,
Remarks
SMPS
P. C.B.
Refer to
Figure 2
D-AMP
P. C.B.
Refer to
Figure 3
Main
P. C.B.
Refer to
Figure 4
D-Amp
P. C.B.
Refer to
Figure 3
Main
P. C.B.
Refer to
Figure 4