LG MCV903 - SECTION 4. CD ELECTRICAL PART; CD ELECTRICAL TROUBLESHOOTING GUIDE

4-1
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
CD ELECTRICAL TROUBLESHOOTING GUIDE
1. CD MAIN PART CHECK
SECTION 4. CD
ELECTRICAL PART
Check Loading
Motor
YES
YES
YES
YES YES
YES
YES
YES
YES
YES
CD FUNCTION
Can the Disc
Insert?
Disc reading
is ok?
Focus/
Tracking/ Sled sig-
nal is OK?
NO NO NO
NO
Check Motor
Drive IC( IC807)
NO
Is Load +,- OK?
Is Motor OK?
(about 12 ohms)
NO NO
OPU driving (Focus
and Tracking) is OK?
Is can’t
see the signal at
Pin 34,35, 36 of
IC807?
NO
Check Vcc of IC807
Is can’t see
the signal( 16.
O344MHz) at Pin 31
of IC807?
NO
Check Cristal
(X802)
Check IC801
input/ output and
control line.
NO
Replace IC801
NO
Replace Cristal
(X802)
Is no signal at SPK?
Refer to
Function check
Is MOT_ Open/
Close OK?
(IC808 Pin 10,11)
Is the PD( CN804
Pin 12) about
180mV ?
Check OPU
(Pick- up)
Check IC808