Troubleshooting - Marantz DV4100F Service Manual

12. TROUBLESHOOTING

TROUBLESHOOTING DISPLAY BOARD
Check supply voltages
NO DISC
The display pcb uses a 24V stabiliser(7112) in combination with a 10V zenerdiode(6102).
POWER ON
Check input voltage: at connector 1115-4:
Check output voltage at anode of Diode 6102:
Check stabilizer 7112 output (VKK):
Check +5Vstb voltage at connector 1115-3:
Check safety resistor R3117
Check +12V at connector 1115-1:
Check filament voltage
NO
AC voltage is created via uP output pin 19 generating a 42kHz (duty cycle 45/55) square
DISPLAY?
signal.
Check frequency : 42kHz
Check buffered square output at emitter of transistor 7105; low level: 800mV, high level:
10.7V
YES
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
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
Check timing and level of segment lines(P1
Diagnostic software "Player script" : Display test.
Check matrix scanning at pin 36 and 37: see test instructions.
NO
Key Function Check matrix scanning at pin 26,27,28,29,30,31,32,33.
Diagnostic software "Player script" : Keyboard test.
YES
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).
NO
Standby LED off?
Check if voltage at connector 1117-1 is 3.33V during standby (light).
Diagnostic software "Player script" : LED test.
YES
Check presence of high pulses at pin 23 of IC7104 while pressing a key on remote control.
Check IR receiver 6610.
NO
Remote control?
Check safety resistor R3131.
Diagnostic software "Player script" : Remote control test.
YES
DISPLAY PCB OK.
-40V 5%
-10V 5%
-34V 7%
+5V 5%
+12V 10%
10%
10%
G14): see test instructions grid lines.
P10): see test instructions segment lines.
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TROUBLESHOOTING A/V BOARD
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"
AUDIO PART
NO SOUND ON
AUDIO CINCH 1402
To put set in "Player script", press keys
Diagnostic Software
STOP+OPEN/CLOSE simultaneously and connect to
APP SND-2
mains. Proceed until display shows "
NO
Check supply voltages 3V3(7400), +8Vaud(7304), -8Vstby,
POWER SUPPLY?
+12Vstby
Check flex connection to mono board.
YES
PCM_OUT0 NO
Check testpoints 7, 8, 9, 10
LRCLK, SCLK
Check flex connection to mono board
PCM_CLK
Check mono board
YES
AUDIO NO
Check DAC IC 7401
TP 12?
Check VREFA on pin 30 of DAC 7401
YES
AUDIO NO
Check OPAMP 7403
CINCH OUTPUT
Check KILL transistors 7404, 7405, 7406, 7407
TP 13?
YES
Check ELCO'S 2456, 2462
Check OPAMP 7403
NO
Check KILL transistors 7404, 7405, 7406, 7407
LEVEL OK?
Check resistors 3453, 3464
YES
Check DAC IC 7401
YES
Check C2455, C2459, C2461, C2464 NP0 TYPE?
DISTORTION?
Check OPAMP 7403
N0
SOUND OK
APP SND-2 " .
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