NAD T 751 Service Manual page 20

B.
No disc
Power on
Does tray open or close?
YES
Fig.1. SLED Driver waveform
Does the pick-up
slide inner or outer
track?
YES
Fig.2. Focus Driver waveform
Does
the pick-up lens move up
and down?
YES
Slide the pick-up to
inner track.
END
Check loading Part.
NO
Push Pick-up to inner track to
the end by hand.
PMD03 Pin 6 change
high to low?
YES
the open/close key
repeatedly, check the voltage of IC2M1
Pins 13, 14 change
YES
the voltage change
at PMD03 Pins 15, 16 more than
2V on the basis of
YES
DECK assembly is defective.
NO
Check SLED Driver output.
IC201 Pin 88 IC2M1 Pins 28, 29.
NO
Check Focus Driver output.
(IC201 Pin 83, IC2M1 Pins 37, 38)
Does
NO
Pressing
NO
0V to 5V
Does
NO
3.8V?
IC201 Pin 88 no output : IC201 is defective
IC2M1 Pins 28, 29 no output : IC2M1 is defective
IC201 Pin 83 no output : IC201 is defective
IC2M1 Pins 37,38 no output : IC2M1 is defective
3-9
DECK assembly is defective.
(Limit sw)
check PANTERA Part.
Replace IC2M1.