NAD M2 AH, Service Manual

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board
Check PSUA FUSE701
YES
Check PSUA
Check DSP Board
5VDS RIGHT?
Check IC700 IC701
YES
Check cable from PSUA to DSP
NO NO
Amber LED ON?
No Power or Power shuts off
immediately
3V3 RIGHT?
NO NO
Short circuit of 3V3? Replace U106
Check U110 U301 U302
Check IC523
Check 108M MCLK
Check U131 U118 U120
YES
Check Q104 Q401
Check D402
YES
"NAD M2" shown on VFD?
SPICS SPIBC SPID
YES
NO
+/-53VL&R to AMP
board correct after PSUA
YES
+7.5V -5V on AMP board right?
YES
NO 3V3 3V3C 2V5 1V2
TO IC523 RIGHT?
YES
U351 U130
YES
NO
signal to IC523 correct?
Check IC502 IC503 IC504 IC505
Check IC507 IC508 IC509
board
Check PSUB FUSE800
Check IC800 U802
Check cable from PSUB to AMP
NO
NO
board
Check AMP board IC560 IC561
Check DSP board U128 U129
Check cable from DSP to AMP
K703 Click?
B
module to AMP board
Check Fuse on Main PSU module
Change failed PSU module
Check cables from Main PSU
5
TROUBLE SHOOTING