The Triangular Wave For Focus Servo Does Not Appears; This Disc Motor Clv Servo Is Defective - Denon D-A03 Service Manual

The triangular wave for focus servo does not appears

Is +3.3V applied to pin 6 of IC149 ?
Yes
Does the triangular wave appear at pin 33 on IC149 ?
<Refer to the waveform diagrams on page 32.>
Yes
Does the triangular wave appear at pin 13 on IC145 ?
<The same waveform as above>
Yes
Does the saw tooth wave appear between pins 13 and 16 of
IC145 ? <Refer to the waveform diagrams on page 32.>
Yes
Does the saw tooth wave appear between pins 13 and 16 of
CX151 ? <The same waveform as above>
Yes
The connection of CX151 is poor or the optical pickup is defective.

This disc motor CLV servo is defective

Does the disc motor rotate in the CD test mode 3 ?
Yes
Does the disc motor rotate too rapidly or slowly ?
Yes
Does the eye pattern appear at pin 19 on IC146 ?
<Refer to the waveform diagrams on page 31>
(It is OK even if the waveform is not clear.)
Yes
Is the eye pattern Vp-p 1.2V inputted to the pin 24 on IC149 ?
Yes
IC149 is defective.
(After checking the parts around it, replace it.)
No
The +3.3V line of IC149 is defective.
No
Check the parts around pin 33 on IC149. If OK, IC149 is
defective.
No
The connection of signal lines between pin 33 on IC149
and pin 13 on IC145 is poor.
No
Check the parts around IC145 and the power supply line. If
OK, IC145 is defective.
No
The PWB pattern has been cut.
No
Is the voltage applied
between pins 27 and 28 of
IC1 for about 0.3-1.5 seconds
when switching from the CD
test mode 2 to 3 ?
No
Is the pin 41 on IC149 in the
high state for 0.3-1.5
seconds and does it pulse
when switching from the CD
test mode 2 to 3 ?
<Refer to the waveform
diagrams on page 31>
Yes
IC149 is defective or wires have broken.
No
Recheck whether the optical pickup objective is dirty.
If it is dirty, clean it.
Check the connection between pin 19 on IC146 and pin 24
on IC149. If OK, the optical pickup is defective.
No
Check the PWB pattern and C155.
D-A03
Yes
The disc motor is
defective or wires
have broken.
0.3-1.5 seconds
No
IC149 is defective.
5V
0.3-1.5 seconds
29