NAD D3020 - Troubleshooting; Troubleshooting Guide

TROUBLESHOOTING GUIDE
Connect AC Cord from D3020
IS THE AMBER LED LIGHTED?
NO
YES
IS IT RED?
CHECK THE 5V SUPPLY CIRCUIT
CHECK THE LED CONTROL CIRCUIT
,AND PROTECET CIRCUIT
YES
THE UNIT WORK NORMALLY?
CAN PRESSING STB TOUCH KEY MAKE
NO
ARE ALL POWER SUPPLIES OK? CHECK THE 5V SUPPLY CIRCUIT
NO
YES
IS THE AMBER LED WHITE?
YES
IS THE STANDBY SINGAL LOW
CHECK THE PROTECT CIRUIT
CHECK THE STANDBY CONTROL
YES
NO
YES
SOURCE KEY IS USELESS?
YES
CHECK MCU CONTROL CIRCUIT
NO
CHECK TOUCH BOARD AND
THE CONNECTORS
YES
IS THE SPK OUT NORMAL?
NO
IS THE OUTPUT DC LEVEL NORMAL?
CHECK PREAMP OUT DC OR
UcD102 MODULE BROKEN?
IS THERE SIGNAL OUTPUT?
YES
YES
NO
CHECK UcD102 MODULE
IS UcD102 MODULE INPUT
SEYON
NORMAL?
CHECK THE MUTE CONTROL
IS THE MUTE SIGNAL OFF?
YES
CHECH NJW1194 AND PREAMP
IS NJW1194 OUTPUT NORMAL?
YES
CHECK CS42528'S FILTER CIRCUIT
IS CS42528 OUTPUT NORMAL?
YES
CIRCUIT
NO
NO
NO
NO
AMP CIRCUIT
CHECK CS42528 AND ITS
INPUT CIRCUIT
IS THE THD HIGH OR ABNORMAL
YES
IS IT WHITE?
CHECK TOUCH BOARD OR
SOFTWARE ERROR
WAVEFORM?
OPEN THE UNIT FOR OVERALL
CHECK
IS IR NORMAL? CHECK THE IR CONTROL CIRCUIT
IS Bluetooth NORMAL?
CHECK Bluetooth CONNECTION
OR MODULE
IS 12V TRIGGER NORMAL?
CHECK 12V OUT CONTROL CIRCUIT
IS HEADPHONE O/P NORMAL?
CHECK HEADPHONE CIRCUIT
OR CONNECTION
IS "UP GRADE" KEY NORMAL?
IS BASS ON/OFF NORMAL?
YES
CHECK TRIG BOARD OR MCU
CHECK BASS CONTROL CIRCUIT
OK
NO
NO
NO
NO
NO
YES
YES
YES
YESYES
YES
NO
YES
YES
NO
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