NAD C660 Service Manual page 14

Sled operation is abnormal.
Is there
Sled control signal output?
(IC320 pin 85)
YES
Is there
Sled drive voltage input?
(IC203 pin 23)
YES
Is there
Sled drive voltage output?
(IC203 pin 17, 18)
YES
Is there
HALL/SLDOUT signal input?
(IC320 pin82)
YES
Is there
SLED FG signal input?
(IC320 pin97)
YES
OK
NO
Check the connection of IC320
pin 85
Check the connection of IC201
NO
pin 17.
Replace the IC201 (BA5925)
NO
Is Act_Mute signal "L"?
(IC203 Pin9)
YES
Replace the IC203 (BA5983)
Is there HALL 1
NO
signal input (IC206 pin3)
NO
NO
Check the IC201 (BA5925)
•Check the Connector (PN201)
•Replace the SLED Motor.
-14-
NO
Replace the IC320 (MICOM)
NO
Check the connection of IC320
pin 26.
YES
Replace the IC206 (BU4053)