Kenwood DMC-G7R Service Manual page 7

• Normal playback
When the address up to the sector address has been proved to be normal in the test mode.
Is initialization performed normally in case of high reflection
disc normal playback?
No
Is the read-in switch turned on when the optical pickup is
moved to the innermost periphery in NORMAL mode?
(Is the pin 48 of IC401 on L level?)
Yes
Is an attempt tp read repeatebly the TOC section of low
reflection disc made?
Yes
Position check in INNER mode
• Audio playback circuit
Although the playback time display is acting, no sound is given during playback in the normal mode.
Is audio waveform output from IC501 pins 26 and 27?
Yes
Is audio waveform output from IC703 pins 18 and 19.
Yes
Is audio waveform output from J703 pins 4 and 5.
Yes
Check headphones jack,and periphery of headphone.
• The disc motor fails to rotate.
Is waveform observed on the pins 58 and 59 of IC201 in
focus gain rough adjustment step?Is audio waveform Is
Yes
waveform observed on the pins 21 of IC601?
Yes
Do the pins 16 and 21 of IC901 waveform observe?
Yes
Replace the disc motor.
Does the playback time display act?
Yes
No
Check IC201 and IC202 connection line.
Check the lead-in switch SW901, solder joint of mechanism
No
PWB, and the pin 8 of CNS601.
Check whether the disc is new one.
No
Check IC201 pins 76 to 78, pin 80 and IC501 pins 11, 12, 13, 15.
No
Check the pins 5 and 6 of IC703.
No
Check whether there is defective solder joint of audio signal line
No
between IC703 and J703.
Check the periphery of IC201.
No
Replace IC601.
No
Check solder joints of L607, IC201, IC901, CNS601, and flexible
No
PWB.
• Recording/playback operation
Insert a low reflection disc, and ascertain audio output by normal playback, and then set TEST REC mode.
Does the head move down, failing to start record even
when the continuous record mode is set after address?
No
Is RF waveform output TP145 in recording/playback mode?
No
Does level of pins 6 and 54 of IC401 and pin 22 of IC101
change depending on record and playback?
Yes
Is RF pattern output from IC201 pin 60 and CNS201 pin 2?
Yes
Check whether there is any damage in IC101, periphery of
Q101, and laser diode.
Check for defects of IC351 in head drive flexible PWB,
Q351 to 354, head, flexible PWB.
Is audio monitor output given in normal mode LINE IN
record?
No
Is waveform obtained on IC501 pins 3 and 5?
No
Is audio waveform observed on the pins 18 and 19 of
IC703?
Yes
Check whether input waveform is observed on the pins 5
and 6 of IC703.
Check voltage of pins 56 and 57 of IC401, pins 2, 4, 7, and 9 of
Yes
IC851, pins 12 and 13 of CNS601. Check whether disc is
record-inhibited.
Yes
Check periphery of IC401 and IC101.
No
Check for soldering failure of IC201 and CNS201.
No
Check waveforms of pins 111, 12, 14, 15 of IC501, pins 76 to
Yes
79 of IC201.
Check whether the pin 24 of IC501 and the pin 75 of IC401 are
Yes
in H state.
Check whether the pin 8 of IC701 is in H state. Check whether
No
voltage of pins 13 to 15 of IC701 changes when the Record
Volume Up/Down button is pressed