Zenith DVB413 Service Manual page 17

D
Focus ON OK?
Yes
Track On OK?
Disc is play?
E
Proper
No
signals on A, B, C,
D of M3355
Yes
. Proper FE signal
on M3355?
Yes
.Proper SBAD signal
on M3355?
Yes
Check the related circuit
on M3355
No
Proper tracking signal
on M3355?
Yes
Proper
M3355 track signal
on M3355?
Yes
T+ & T- output
properly?
Yes
Check cable connection on
pick-up head.
No
Check RF signal waveform.
3-8
No
Check connections between
M3355 and pick-up head.
No
Check the related circuit
on M3355 FE signal
No
Check the related circuit
on M3355 SBAD signal .
No
Check the related
circuit on M3355
No
Check the track connection
on M3355 and motor driver.
No
Check the tracking control
amp circuit on motor driver.