NAD T748 Service Manual page 71

* T748 HDMI PART TROUBLESHOOTING
CHECK AT POWER
SUPPLY
CHECK AT CN901
PIN1(+12V), PIN5(+5.6V),
PIN9(+2.5V), PIN13(+12V)
O K
CHECK AT IC911, IC912,
IC913, IC917, IC918,
IC915, IC916
CHECK AT CN901
. N G
WAFER & INPUT PCB
REGULATOR & IC
REPLACE
CHECK AT POWER
. N G
SUPPLY CIRCUIT &
IC REPLACE
NO HDMI AUDIO
OUT
CHECK HDMI JACK
IS POWER APPLIED
CORRECTLY TO EACH
POINT?
CHECK AT CN903 PIN
2,3,4,6,7,8,9
CHECK AT
RN950, RN951, RN953
RN953 RN953
CHECK AT IC913
PIN2 ~ PIN9,
PIN11 ~ PIN18
2-86
REPLACE HDMI
. N G
JACK or CONNECT
THE HDMI CABLE
INTO THE JACK
O K
CHECK POWER
. N G
SUPPLY CIRCUIT
(CHECK IC POWER
PIN)
OK
CHECK OPEN
N.G
CIRCUIT or SHORT
CIRCUIT
OK
CHECK OPEN
N.G
CIRCUIT or SHORT
CIRCUIT CIRCUIT
OK
CHECK OPEN
N.G
CIRCUIT or SHORT
CIRCUIT