Method For Diagnosing Degradation Of The Lds On The Pickup Assy - Pioneer DV-470-S Service Manual

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7.1.6 METHOD FOR DIAGNOSING DEGRADATION OF THE LDS ON THE PICKUP ASSY

Case when this diagnosis is required :
When playback of any disc, including a test disc (DVD: GGV1025, CD: STD-905), cannot be performed
How to diagnose
In the case mentioned above, degradation of the laser diodes (LDs) mounted on the 03 SD Pickup Assy-S is suspected.
Measure the voltage between the two ends of one of the resistors mentioned below.
No playback of a DVD :
Measure the voltage between the two ends of R22 or R25 on the DVDM Assy.
If the voltage is 0.4 V or higher, the 650-nm LD is degraded.
No playback of a CD :
Measure the voltage between the two ends of R21 or R26 on the DVDM Assy.
If the voltage is 0.4 V or higher, the 780-nm LD is degraded.
03 SD PICKUP
12
1
5
6
ASSY-S
CN101
6
7
If the measurements show degradation
of an LD, replace the 03 SD Pickup
Assy-S.
Front side
DV-470-S
7
8
B
DVDM ASSY
SIDE A
8
A
B
C
D
E
F
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