LG CJS98F User Manual

3-7
ONE POINT REPAIR GUIDE
NO BOOTING IN CD/USB FUNCTION
After you turn on power key and displayed message in the following order (HELLO  VOL XX  CD
or USB) on VFD, it will not display other message on VFD, and it will not boot-up normally.
3-3. SERIAL FLASH (IC503)
3-3-1. Solution
Please check and replace IC503 on MAIN board.
3-3-2. How to troubleshoot (Countermeasure)
1) If the crystal(X500) does oscillate, check Serial Flash(IC503) on MAIN board.
 Check pin8(VCC), pin6(CLK), pin1(CS), pin2(DO), pin5(DI) of below waveform.
2) If pin1, 2, 5, 6, 8 doesn’t come out, check damping resistor(R54A, R54B, R54C, R54D) of IC503.
 If damping resistor of IC503 is OK, then replace IC503. (it need to download program)
3) After change IC503, if It is still not below waveform, check IC501(DSP IC).
3-3-3. Service hint (Any picture/ Remark)
V
VCC
CLK
DO
CS#
< Signal waveform >
< MAIN board bottom view >
IC503
IC503

LG CJS98F Specifications

General

Brand	LG
Model	CJS98F
Category	Stereo System
Language	English