NAD T517AHT Service Manual page 20

ELECTRICAL TROUBLESHOOTING GUIDE
A
RESET or power on.
Show LOGO?
YES
Does
tray move inside
when it is not at closed
position?
YES
B
Flash
NO
memory operates
properly?
SDRAM
works properly?
MT1389S
VIDEO outputs
properly?
Have TV
signal output?
Check AV cable
connection to TV set.
Normal
NO
TROUT & TRIN
signals?
Normal
TRCLOSE & TROPEN
signal?
Normal
LOAD+ & LOAD-
signal?
Check the cable connection
between main PCBA and loader.
3-7
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
Check connection lines
between FLASH & MT1389S
and the FLASH access time
whether is suitable or not.
Check connection lines
between SDRAM & MT1389S
and the SDRAM is damaged.
Check the related
circuit of MT1389S.
Check the filtering and amp
circuit of TV signal.
Check the load
OPEN & CLOSE switch
Check the tray control I/O
pins on MT1389S & AM5890.
Check the tray control
amplifying circuit on Motor driver.