85
MEP-7000
5
6
7
8
5
6
7
8
A
B
C
D
E
F
5.4 DEFECT JUDGMENT OF THE PICKUP ASSY
LD short-circuit pads
SRV1 ASSY
SRV2 ASSY
*1
*2
*3
The Pickup Assys for the DVD/CD drives are judged as OK if the results of the following 2 items are in the range of the
required specifications. If the pickup is judged as
N
G, replace the Traverse mechanism.
Item
Re
q
uired
specifications
Status of the
unit when tested
Measurement method
Criteria for jud
g
ment
LD current
Actuator
resistance
• Specifications of the
focus side :
3.4±0.5[
Ω
]
• Specifications of the
tracking side :
4.1±0.6[
Ω
]
• DVD : TYP50[mA]
MAX73[mA]
• CD : TYP70[mA]
MAX
8
0[mA]
Connect the
control and drive
units.
Disassemble the
unit and pick out
the DVD/CD
drives.
If the value exceeds the
maximum value, the LD is
degraded.
Check the “CURRE
N
T
VALUE,”*1 as indicated in
“[4] LD STATUS” of “6.2
SERVICE MODE FOR THE
DRIVE U
N
IT.”
N
ote 1: If the short-circuit
pad of the LD is short-
circuited, open it.*2
N
ote 2: Check the mounting
status of the following
resistors:
• SRV 1
R104~R107,R10
8
~R111
• SRV 2
R904~R907,R90
8
~R911
If the measurement values are
outside the range of the
specifications, the pickup is
judged as
N
G.
Before disconnecting the
FFC cable from the SRV
Assy, short-circuit the two LD
short-circuit pads (for CD
and DVD) to prevent excess
LD current to flow. Then
measure the actuator
resistance. After measure-
ment, be sure to open the LD
short-circuit pads.*2
• Focus side: Disconnect the
FFC cable from the
C
N
100/900,*3 then
measure the resistance
between Pins 1 and 2 of the
FFC.
• Tracking side: Disconnect
the FFC cable from the
C
N
100/900,*3 then
measure the resistance
between Pins 3 and 4 of the
FFC.
