NAD L55
Manual de Servicio

C.
DISC IN

OPEN/CLOSE

Fig.3. FOCUS ERROR waveform NO FOCUS ON? YES
Check the focus error moving the lens up and down. (IC2A1 Pin 42)

NO

Check IC2A1 Pin 11,12,13,14 in DVD Mode IC201 no output : Pick-up is defective.

YES

Does the TTL level change at IC201 Pin 78 and 132 moving the lens?

NO Replace IC201.

YES

Replace µ-COM or IC201.

NO Does the disc turn? YES

Check IC2M1 Pin 21, PMD03 Pin 6 turn when the IC2M1 Pin 21 is less than 2.2V.

Check IC201 and IC2M1 when PMD03 Pin 6 is abnormal

NO IC201 Pin169 is "High"? YES Check A

Is OK the track jump. YES

NO

Does the signal pulse appear at IC2A1 Pins 39, 29? YES

NO

IC2A1 is defective.

NO Does the screen appear? YES

Video Part is defective. Check "5.MPEG Circuit." Check "7.OSD/Video Circuit."

Replace µ-COM part.

END

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