Philips DVD737, Service Manual

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3-6
Touble Shooting charts
No RC and FTD Display
Front board no function FTD
no display or Remote
control no function
Check Power
supply to Front
board
Put the Mains switch to ON
1. Check supply voltage at connector
1101
Pin 1
--> Gnd
Pin 2 --> +12V
Pin 4 --> +5V
Pin 5 --> -24V
2. Check / Replace cable connection to
con 1101
3. Check / Replace Power Supply Unit
NO
Check IR signal
at pin 5 of con
1104 of Front Bd
with a Remote
YES
1. Check +5V to pin 2 of IR receiver
7101 on the Front board
2. Check / Replace resistor 3113.
3. Check / Replace IR receiver IC 7101
on the Front board
NO
Check VFD
controller grid
and segment
output
YES
1. Check +5V supply at pin 14 of
IC 7100 on Front Board
2. Check /Replace R3100 and R3102
3. Check VEE voltage at pin 27 of
IC 7100 -->
-24V
4. Check serial data input at pin 6/8/9 of
VFD controller IC 7100
5. Check / Replace VFD controller IC
7100 on the Front Bd
NO
YES
YES
Check filament
voltage VGL+1 &
VGL-1 to FTD
1. Check filament voltage at FTD
Pin 1/2 --> -18Vdc (2.6Vac across)
Pin 31/32 --> -18Vdc (2.6Vac across)
2. Check / Replace R3101 and D6100
on the front board
3. Check / Replace FTD display 1100 on
the Front board
NO
1. Check pulses at pin 15/16 of VFD
controller IC 7100
2. Check / Replace diode D6102 and
D6103 on the front bd
3. Check / Replace VFD controller IC
7100 on the Front bd
Check local
keyboard key
functionality
NO
YES
END
PM3380B
1 T
Pin 15
10V / AC
2ms / div
10V / AC
2ms / div
Pin 16
PM3380B
ch1
1 T
IR SIGNAL
1
ch1
2V / div DC
2ms / div
ch1