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Internal Use Only Website http://biz.lgservice.com CAR CD/MP3/WMA RECEIVER SERVICE MANUAL MODEL : LAC2900N CAUTION BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL. P/NO : AFN73228921 JUNE, 2009...
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 12V Speaker impedance 4Ω Ground System Negative Dimensions (W x H x D) 180 x 50 x 176 mm (Without Control Panel) Net Weight 1.3kg • TUNER Frequency Range 87.5 ~ 107.9, 87.5 ~ 108MHz S/N Ratio...
FIRMWARE UPGRADE METHOD [ MAIN/CD FIRMWARE UPGRADE ] 1. Confi rmation of version information • Change the Source of audio set to tuner. (Default: tuner) • Turn power off using power key. • Press power key for 5 sec. (After power on, continue pressing) •...
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 CN301(16,15) Vdd and Gnd? Checked the Regulator IC301(15,14) Back up Vdd ? Checked the Main Micom...
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Not available to Volume control? Checked the RV901, CN901(2,4), IC402(82,83) Encoder Volume? Checked the IC402(9,10), IC802(25,26) Volume IC control? Not available to Key Control? Checked the SW902~SW918 Tact switch? Checked the CN901(11,13), IC402(53,54) Key line? Not available to ANT(Motor Type) Control? Checked the D430, IC301(12,13), IC402(33) ANT 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? Checked the E-VR IC802(1,2,3,4,5,6,7,9,18,19,20,21,22,23) Signal in/out? Checked the...
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Hearing the Pop Noise? IC402(14,15,23,32), IC802(15) Checked the IC801(22), Q601, Q602, Q603, Q604,Q605, Mute Contorl? Q606, Q607, Q608, Q609, Q610 Checked the TU201(8), IC402(7) AF mute? No output Beep sound? Checked the IC402(80), IC802(14) Beep Control?
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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? Checked the LCD IC901(56) Driver Vdd? Checked the LCD IC901(60) Driver Ground? Checked the LCD IC901(57), IC402(79) Driver RESET? Checked the LCD IC901(61) Driver OSC? Checked the LCD...
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Not available to illumination with button? Checked the Dimmer CN302(7), IC301(9) control input? Checked the IC301(4) LED Vdd? Checked the LD901, LD904~LD919 RED LED?
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Don't moved Level dancing bar? Checked the Level IC802(17), IC402(57) Meter Signal Input? Not avaliable to LCD Lighting control Checked the Dimmer CN302(7), IC301(9), D423, IC402(43,49) control input? Checked the IC301(4), Q305, CN901(16) LCD Vdd? Checked the LCD Q317, IC402(41) Vdd control? LD902, LD903 Checked the LED?
4. TUNER ERROR CORRECTION FLOW CHART Something wrong with the Tuner system? Not available to Tuner? Checked the TU201(6,17), Q302, IC301(10,14) Tuner Vdd? Checked the Tuner IC402(40), Q307, IC301(11) Vdd control? Checked the TU201(3,7,12,16) Tuner Ground? Checked the TU201(14,15), IC402(34,36) I2C data? Checked the TU201(1,2)
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Tuner no sound? Checked the TU201(10,11), IC802(5,6) Tuner Signal out? Checked TU201(8), IC402(7) the AF mute? Checked the See the Sound Error correction Process. E-VR & Power AMP? Not available to AF? Checked the TU201(4), IC402(56) S-METER level? Checked TU201(19,20), IC402(5,6) the RDS data? Not available to RDS function? Checked...
5. CDP ERROR CORRECTION FLOW CHART Something wrong With the CD Player? No Loading? CN520(12,16) Checked the CD Vdd? Checked the CD IC503(28,42,60,72,81,123,143) DSP Ground? Checked the Motor IC504(7,8,20) DRV VDD? Checked the CD IC504(88) DSP Reset? Checked the CD X501 DSP X-tal? Checked the Disc in...
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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(19,21) LODING Control? Fig 3, 4 Checked the CD IC503(84,85,86,87) DSP Control? Fig 10~ 11 Checked the IC503(38), IC504(15,16) focus Control? Fig 5...
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CD no sound? Checked the IC503(140,141) DSP signal out? No ejected the CD? Checked the IC402(54) Eject key? Checked the Loading CN520(19,21) Motor Control? Fig 3,4 2-13...
6. AUX ERROR CORRECTION FLOW CHART Something wrong With the AUX? AUX no sound? Checked the AUX JK901, CN901(6,10), L901, L902, R603, R604 Signal input? Checked the See the Sound Error correction Process. E-VR & Power AMP? 2-14...
• WAVEFORMS Fig.1) SWITCHING CONDITION FOR LOADING Fig.2) SWITCHING CONDITION FOR UNLOADING CN520:[PIN7] CN520:[PIN7] CN520:[PIN30] CN520:[PIN30] CN520:[PIN29] CN520:[PIN29] LOADING S/W LOADING S/W CN520:[PIN27] CN520:[PIN27] 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:[PIN19] CN520:[PIN19]...
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Fig.7) SPINDLE CONTROL SIGNAL Fig.8) SLED CONTROL SIGNAL IC503:[PIN41] IC503:[PIN40] IC503:[PIN25] IC504:[PIN13] IC504:[PIN11] IC504:[PIN14] IC504:[PIN12] SPOUT SLOUT Fig.9) MD, RFOUT, LD Fig.10) DI, DO, CL, CE CN519:PIN[15] IC503:DO(PIN87) IC503:PIN[8] IC503:DI(PIN86) CN519:PIN[16] IC503:CL(PIN85) IC503:CE(PIN84) RFOUT Fig.11) DI, DO, CL, CE [Detail] Fig.12) FSEQ, WRQ IC503:DO(PIN87) CN520:(PIN24)
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2-2. PIN DESCRIPTION Enable Output Name in Micom Name in Model Description setted Format P60/SCL0 EEPROM_CLK(O) N-CH B/T EEPROM CLOCK OUT P61/SDA0 EEPROM_DATA(O) N-CH B/T EEPROM DATA OUT PLL_CLK(O) N-CH CLK output for PLL IC PLL_DATA(O) N-CH Data input for PLL IC P31/TI03/TO03/INTP4 RDS_CLK(I) From tuner pack, RDS CLK input...
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Enable Output Name in Micom Name in Model Description setted Format P111/VNO1 LCD_LIGHT(O) CMOS LCD Light control AVREF0 AVREF0 • D/A converter reference voltage input • Positive power supply for P110, P111, and D/A converter AVSS AVSS Ground Potential for Ports P157/ANI15 WIREDREMOCON_ADIN(I) Wired RMC line input...
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4-3. PIN DESCRIPTION Pin No. Pin Name Pin Description Input for loading forward Input for loading reverse LDCONT Output control terminal for loading Control terminal for power saving mode Input 1 of CH1 Input 2 of CH2 PREVCC Pre and loading unit power supply input terminal POWVCC12 Power unit power supply input terminal (CH1, CH2) VOL ( - )
6. IC802 (BD3702FV) 6-1. BLOCK DIAGRAM 6-2. 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...