Troubleshooting A Guide - NAD M12 Service Manual

No Pow er or Pow er shuts off
immediately
NO
Amber LED ON?
YES
Touch Pow er key
NO
LCD Display ON?
YES
Connect USB cable to computer
Computer found hardw are NO
and M12 LCD
Display sample rate
YES
B

TROUBLESHOOTING A GUIDE

Check Sw itching Mode
Pow er Supply RIGHT?
YES
Check MDC Board
3V3S RIGHT?
Check U3058
Check FPP&LCD board
5V3F(5V3D) correct?
YES
SPI signal to FPP
correct?
YES
Change FPP board
Check U400 U401
Check J7003
Check U3071 U3060
Check driver on computer
NO
Change SMPS
NO
Short circuit of 3V3s?
Check U3064 U3052 U3053 U3054
U3055 U3056 U3057 U3059 U3060
Check Touch board and cable
NO
short circuit on 5V3F(5V3D)
3V3?
Check U3065 U3066 U1038 U1039
Check U1041 U1042 U9001
Check U9002 U9003 U9004 U9006
NO
Check U3058
10
NO
Replace U3064
NO
Check Q1 U7