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Internal Use Only Website http://biz.lgservice.com CAR CD/MP3/WMA RECEIVER SERVICE MANUAL MODEL: LCS500UN CAUTION BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL. P/NO : AFN74552074 DECEMBER, 2010...
SECTION 1 SUMMARY SERVICING PRECAUTIONS 1. Always disconnect the power source before: 1) Removing or reinstalling any component, circuit board, module or any other instrument assembly. 2) Disconnecting or reconnecting any instrument electrical plug or other electrical connection. 3) Connecting a test substitute in parallel with an electrolytic capacitor in the instrument. CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard.
ESD PRECAUTIONS Electrostatically Sensitive Devices (ESD) Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components com- monly are called electrostatically sensitive devices (ESD). Examples of typical ESD devices are integrated circuits and some fi eld-effect transistors and semiconductor chip components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity.
SPECIFICATIONS • GENERAL Output Power 53 W x 4 CH (Max.) Power Source DC 12 V Speaker impedance 4 Ω Ground System Negative Dimensions (W x H x D) 178 x 50 x 169 mm (Without Control Panel) Net Weight 1.22 kg •...
LOCATION OF USERS CONTROLS FRONT PANEL A [SRC] Selects function sources. I [ ] Releases a disc. [• OFF] Power on/off. J [ ] Opens the front panel. B [MENU] Activates setting menu. K [Mute] C Volume knob Temporarily stops the sound. •...
FIRMWARE UPGRADE METHOD [ MAIN AND CD/USB FIRMWARE UPGRADE ] 1. Confi rmation of version information 3. Upgrade start • Change the Source of audio set to tuner. • In order to start upgrade, (Default: tuner) Press Preset 1 Key, LCS Model •...
HOW TO CONNECT AUDIO SET TO POWER SUPPLY • It is suffi cient only to supply power for upgrade. • Shown from the right fi gure, connect yellow line (Battery) and red line (Ignition) to plus and minus terminal respectively. •...
SECTION 2 ELECTRICAL ELECTRICAL TROUBLESHOOTING GUIDE & WAVEFORMS 1. SYSTEM CONTROL ERROR CORRECTION FLOW CHART Something wrong with the system control? No power? F301 Inside of CN302 Checked the Fuse? Checked the Back up CN302(1, 2, 3) Vdd and Gnd? Checked the Regulator IC301(15, 14) Back up Vdd ?
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Not available to Remocon? Checked the RC902, R961 Remocon Sens Vdd? R962, IC402(81), Checked the LCS Series : PN901(1) Remocon Sens line? LCF Series : PN902(24) Not available to Volume control? EV901, IC402(82, 83), Checked the LCS Series : PN901(6, 7) Encoder Volume? LCF Series : PN902(18, 19) Checked the...
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Not available to Telephone Mute? Checked the Tel ZD499, Q312, Q326, IC402(34) Mute input? Checked the IC402(14, 15), IC802(15) Mute Control? Not available to ANT(Motor Type) Control? Checked the D430, IC301(12, 13), IC402(33) ANT control? Not available to Remote(Power AMP) control? Checked the CN302(8), Q320, Q319, IC402(36) Remote control?
2. SOUND ERROR CORRECTION FLOW CHART Something wrong with the Sound? No sounds of All Functions? Checked the IC802(24) E-VR Vdd? Checked the IC802(27) E-VR Ground? Checked the IC802(25, 26), IC402(9, 10) E-VR Control? Checked the E-VR IC802(15), IC402(15) Mute Control? IC802(1, 2, 3, 4, 5, 6, 7, 9, Checked the E-VR 18, 19, 20, 21, 22, 23)
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Hearing the Pop Noise? IC402(14, 15, 32), IC802(15), Checked the IC801(22), Q603, Q604, Q605, Q606, Q608 Mute Contorl? No Sound External AMP? Checked the IC802(18, 19, 20, 21, 22, 23) Line Out Signal? Checked the Line Out Q603, Q604, Q605, Q606, Q608, IC402(15) AMP Mute Control? Checked the Line Out JK601...
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■ CAUTION - Tip for repair Before exchange power amp IC(TB2946) for no audio problem, you have to check below list. 1. Check VCC (pin 20, 6) & GND 2. Check input pin 11, 12, 14, 15 OUT1 + 3. Check Standby, pin 4 PW-GND1 : Follow the below list.
3. DISPLAY ERROR CORRECTION FLOW CHART Something wrong with the Display? No Display or Some Display is broken? LCS Series : IC901(56) Checked the LCD LCF Series : LCD901(7) Driver Vdd? LCS Series : IC901(60) Checked the LCD Driver Ground? LCF Series : LCD901(10) Checked the LCD LCS Series : IC901(57), IC402(79)
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Not available to illumination with button? Checked the Dimmer CN302(7), IC301(9) control input? Checked the IC301(4), Q303, IC402(61) RED LED Vdd? LCS Series : LD921~LD945 Checked the LCF Series : LD921~LD936 RED LED? Checked the IC301(4), Q304, IC402(43) BLUE(GREEN) LED Vdd? LCS Series : LD951~LD975 Checked the BLUE(GREEN) LED?
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Not available to LCD Lighting control? Checked the Dimmer CN302(7), IC301(9) control input? Checked the IC301(4), Q302, IC402(49) White LED Vdd? LCS Series : LD991, LD992 Checked the White LED? LCF Series : LD990~LD993...
5. CDP ERROR CORRECTION FLOW CHART Something wrong with the CD Player? No Loading? CN520(14, 12) Checked the CD Vdd? IC501(4, 5, 7, 9, 12, 44, 49, 51, 74, 77, 81, Checked the CD DSP Ground? 102, 104, 116, 117) Checked the Motor IC504(7, 8, 20) DRV Vdd?
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No Reading & "FILE CHECK" Display? Checked the CN506(8) Limit Switch? Fig 1, 2 Checked the Motor IC504(21) DRV Mute Control? Checked the Motor CN520(21, 23) Loading Control? Fig 3, 4 Checked the CD CN520(1, 3, 4, 5) DSP Control? Checked the IC501(111), IC504(15, 16) Focus Control?
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CD no sound? Checked the IC501(46, 47) DSP signal out? No ejected the CD? Checked the IC402(54) Eject key? Checked the Loading CN520(21, 23) Motor Control? Fig 3, 4 2-13...
6. USB ERROR CORRECTION FLOW CHART Something wrong with the USB? Only "NO USB" or "USB CHECK" Display? IC302 Checked the USB Vdd? IC501(4, 5, 7, 9, 12, 44, 49, 51, 74, 77, 81, Checked the USB interface IC Ground? 102, 104, 116, 117) Checked the USB CN520(19)
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"FILE CHECK" Display? IC501(4, 5, 7, 9, 12, 44, 49, 51, 74, 77, 81, Checked the CD DSP Ground? 102, 104, 116, 117) Checked the USB CN520(19) interface IC Reset? Checked the X501 DSP X-tal? Checked the CN520(1, 3, 4, 5) DSP Control? USB no sound? Checked the CD...
7. BLUETOOTH ERROR CORRECTION FLOW CHART (OPTIONAL) Something wrong with the BT? No pairing? Checked the See the manual phone list. BT phone list? Checked the BT CN403(13) module Vdd? Checked the BT CN403(14) module 5 V? Checked the BT IC402(1, 2, 71, 72) module data interface? No sound?
8. AUX ERROR CORRECTION FLOW CHART Something wrong With the AUX? AUX no sound? LCS Series : JK903, IC802(7, 9), CN901(15, 17, 19), PN901(3, 4, 5) Checked the AUX LCF Series : JK903, IC802(7, 9), Signal input? CN971(20, 21, 22), PN902(20, 21, 22) Checked the See the Sound Error correction Process.
• WAVEFORMS 1. MAIN PART 1) MICOM(IC402) ↔ BLUETOOTH MODULE(CN403) IC402:[PIN71] IC402:[PIN72] 2) MICOM(IC402) ↔ DISPLAY (LCS SERIES : CN901, LCF SERIES : CN902) IC402:[PIN46] IC402:[PIN44] IC402:[PIN74] IC402:[PIN79] 3) MICOM(IC402) ↔ TUNER IC(IC101) IC402:[PIN4] IC402:[PIN3] 4) MICOM(IC402) ↔ VOLUME IC(IC802) IC402:[PIN9] IC402:[PIN10] 2-18...
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2. CDP PART Fig.1) SWITCHING CONDITION FOR LOADING Fig.2) SWITCHING CONDITION FOR UNLOADING CN506:[PIN2] CN506:[PIN2] CN506:[PIN1] CN506:[PIN1] CN506:[PIN8] CN506:[PIN8] LOADING S/W LOADING S/W CN506:[PIN11] CN506:[PIN11] 12/8 S/W 12/8 S/W LIMIT S/W LIMIT S/W CHUCKING S/W CHUCKING S/W Fig.3) MOTOR CONTROL SIGNAL FOR LOADING Fig.4) MOTOR CONTROL SIGNAL FOR UNLOADING CN520:[PIN21] CN520:[PIN21]...
• CIRCUIT VOLTAGE CHART IC101 IC301 IC801 PIN NAME VOLTAGE PIN NAME VOLTAGE PIN NAME VOLTAGE TUNER Mode Mode MODE MODE MODE MODE PWR_GND AMRFIN STBY AMRFDEC FREG_B 13.6 FMIN2 FREG_F 1.24 FMIN1 ILL_8.4 14.3 GNDRF CTL4(FREG) PWR_GND VCC2 CD_8 V AMRFAGC DSP_3.3 V LOUT...
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IC802 CN402 CN403 PIN NAME VOLTAGE PIN NAME VOLTAGE PIN NAME VOLTAGE CD_R BT_L CD_L AGND AGND BT_R BT_R BT_L BT_TX TUNER_R DGND TUNER_L AGND 3.259 BT_RX AUX_R LOAD_SW EEPROM_SDA 4.99 EEPROM_SCL AUX_L LG2TA 4.98 AGND 4.98 MUTE TA2LG 8.05 VDD_3.3 V BEEP 3.3 V...
3. IC802 (BD3702FV) 3-1. BLOCK DIAGRAM 3-2. PIN DESCRIPTION Terminal Terminal Terminal Terminal Description Description Name Name A input terminal of 1ch MUTE External compulsory mute terminal A input terminal of 2ch LRST Level meter reset terminal B input terminal of 1ch LOUT Output terminal for Level meter B input terminal of 2ch...
BLOCK DIAGRAM LINE-OUT BLOCK LINE_OUT : 2V RL/SW RR/SW TUNER-On-Board NXP Tiger-RDS(IC101) RL/RR : LINE_OUT SUBWOOFER OPTION TEL MUTE PLL TUNING POWER SUPPLY AM TUNER I2C BUS SYSTEM 2.2K 2.2K TELMUTE_3.3V SIGNAL STEREO DECODER IMPROVEMENT 2.2K HIGH CUT FM TUNER CONTROL SOFT MUTE DEMODULATOR...