LG CM4540 Service Manual

5. PWM MODULATION CHECK
PWM MODULATION PART CHECK
Check
CN501 Pin7,8
(5.6 V)
• Check IC601(TAS5548)
VDD 3.3 V - Pin9,14.35,50.
• Check X601 (12.288 MHz).
NO
Refer to
SMPS troubleshooting.
Check
X601(12.288 MHz)
operation.
NO
Replace X601(12.288 MHz).
Check X601
(12.288 MHz).
OK
YES
NO
Check
IC601 Pin21 CLK
input.
Check IC501
(MLC3730)
Pin B3: RESET
Pin A1: SDA
Pin A2: SCL
output.
NO
Replace R53E,R53C,R53B.
Check line
resistor output
RST: R53E / SCL: R53C /
SDA: R53B.
NO
YES
YES
YES
YES
YES
YES
OK
YES
A
3-22
AUDIO ELECTRICAL TROUBLESHOOTIHG GUIDE

LG CM4540 Specifications

General

Brand	LG
Model	CM4540
Category	Stereo System
Language	English