Failure Judgement Of The Pickup Assy - Pioneer CDJ-2000 Service Manual

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5.2 FAILURE JUDGEMENT OF THE PICKUP ASSY

LD power after passing through the objective lens [mW]
SPEC: DVD 0.180 ±0.03
CD 0.210 ±0.03
Check method: Measure the LD power, using an optical power meter.
Failure judgment: A value out of the range of the specifications is judged as failure.
LD current [mA]
SPEC: DVD TYP50 MAX70
CD TYP65 MAX75
Check method
Measure the LD current at the probe pad on the SRVA Assy, using a tester.
[Detailed check method]
1. For details on how to emit light from the LD, see the "[5] Confirmation of movement of the drive unit" in 6. SERVICE MODE.
2. With the LD OFF, apply the probes of a tester to the reference probe pad and 78CHK (65CHK). (CD: 78CHK/DVD: 65CHK)
Note: Be careful not to apply the probes to the pads with LD ON. If you do so, the LD may be damaged.
3. With the probes applied to the above-mentioned pads, turn the LD ON to measure the voltage between them.
4. After measurement, turn the LD OFF (ALL OFF) then pull the probes away.
5. Calculate the current value by dividing the measured voltage value by the resistance value.
(Resistance values to be used: CD: R7008 = 22 ohms, DVD: R7007 = 12 ohms)
Failure judgment: If the calculated current value exceeds the maximum value, the LD has been degraded
Fig.1 SRVA Assy
Actuator resistance value [ohms]
Specifications on the focus side: 3.7 ±0.55
Specifications on the tracking side: 4.3 ±0.65
Check method: Disconnect* the FFC connected to the CN7001 on the focus side then measure the resistance value
between FFC pins 23 and 24.
Disconnect* the FFC connected to the CN7001 on the tracking side then measure the resistance value
between FFC pins 21 and 22.
*Short-circuit the LD short-circuit pad. (Refer to the "TM Assy-S" in 7. DISASSEMBLY.)
Failure judgment: A value out of the range of the specifications is judged as failure.
5
6
78CHK
65CHK
Reference probe pad
CDJ-2000
6
7
7
8
A
B
C
D
E
F
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