Yamaha DVD-S510, Service Manual, Page: 21 / 78

DVD-S510/DV-S5350
20
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TROUBLESHOOTING
Display board
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 7110.
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 zener diode(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
NO