Electrical diagrams and Print-layouts
38
DVD 950
6.
Figure 6-1
DISPLAY PCB OK.
NO DISC
POWER ON
DISPLAY?
•
Check presence of high pulses at pin 23 of IC7104 while pressing a key on remote control.
•
Check IR receiver 6610.
•
Check safety resistor R3131.
•
Diagnostic software “Player script” : Remote control test.
•
Check if voltage at connector 1117-1 is 4.9V when power on (no light)
•
Check if voltage at base of Tr 7109 is 4.9V when power on (no light).
•
Check if voltage at connector 1117-1 is 3.33V during standby (light).
•
Diagnostic software “Player script” : LED test.
•
Check matrix scanning at pin 36 and 37: see test instructions.
•
Check matrix scanning at pin 26,27,28,29,30,31,32,33.
•
Diagnostic software “Player script” : Keyboard test.
•
Check supply voltages
⇒
The display pcb uses a 24V stabiliser(7112) in combination with a 10V zenerdiode(6102).
⇒
Check input voltage: at connector 1115-4:
-40V
±
5%
⇒
Check output voltage at anode of Diode 6102:
-10V
±
5%
⇒
Check stabilizer 7112 output (VKK):
-34V
±
7%
⇒
Check +5Vstb voltage at connector 1115-3:
+5V
±
5%
⇒
Check safety resistor R3117
⇒
Check +12V at connector 1115-1:
+12V
±
10%
•
Check filament voltage
⇒
AC voltage is created via uP output pin 19 generating a 42kHz (duty cycle 45/55) square
signal.
⇒
Check frequency : 42kHz
±
10%
⇒
Check buffered square output at emitter of transistor 7105; low level: 800mV, high level:
10.7V
⇒
Check DC decoupling: check RMS voltage between FIL1 and FIL2 lines:
3.9Vrms<Vfil<5.2Vrms
The Vfil_DC level at kathode of diode 6101 should be –25.8V
±
10%
•
Check oscillator frequency of 8MHz at pin 8 of IC7104
•
Check reset circuit around transistor 7108: see test instructions of reset circuit.
•
Check timing and level for all grid lines(G1
→
G14): see test instructions grid lines.
•
Check timing and level of segment lines(P1
→
P10): see test instructions segment lines.
•
Diagnostic software “Player script” : Display test.
NO
YES
Key Function
NO
YES
Standby LED off?
YES
Remote control?
NO
YES
TROUBLESHOOTING DISPLAY BOARD
NO
CL 96532065_057.eps
130799
Figure 6-2
Testing of A/V board can be done using diagnostic software “Player script”.
Mono board is used to generate a sinus with the soundtest SND-2 or a VIDEO signal with the picture test PIC-1.
See description in chapter “Diagnostic Software : Script Interfaces”
SOUND OK
Diagnostic Software
NO SOUND ON
AUDIO CINCH 1402
POWER SUPPLY?
•
Check DAC IC 7401
•
Check C2455, C2459, C2461, C2464 NP0 TYPE?
•
Check OPAMP 7403
•
Check ELCO'S 2456, 2462
•
Check OPAMP 7403
•
Check KILL transistors 7404, 7405, 7406, 7407
•
Check resistors 3453, 3464
•
Check OPAMP 7403
•
Check KILL transistors 7404, 7405, 7406, 7407
•
Check DAC IC 7401
•
Check VREFA on pin 30 of DAC 7401
•
Check testpoints 7, 8, 9, 10
•
Check flex connection to mono board
•
Check mono board
•
Check supply voltages 3V3(7400), +8Vaud(7304), -8Vstby,
+12Vstby
•
Check flex connection to mono board.
NO
YES
PCM_OUT0
LRCLK, SCLK
PCM_CLK
NO
YES
NO
YES
AUDIO
CINCH OUTPUT
TP 13?
NO
YES
AUDIO
TP 12?
NO
YES
LEVEL OK?
YES
N0
DISTORTION?
•
To put set in “Player script”, press keys
STOP+OPEN/CLOSE simultaneously and connect to
mains. Proceed until display shows “
”.
TROUBLESHOOTING A/V BOARD
AUDIO PART
APP SND-2
APP SND-2
CL 96532065_059.eps
130799