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Internal Use Only Website http://biz.lgservice.com Mini Hi-Fi System SERVICE MANUAL MODEL: RAD225B (RAS225B) CAUTION BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL. P/NO : AFN73972629 MARCH, 2010...
SECTION 1. GENERAL SERVICING PRECAUTIONS NOTES REGARDING HANDLING OF THE PICK-UP 1. Notes for transport and storage 1) The pick-up should always be left in its conductive bag until immediately prior to use. 2) The pick-up should never be subjected to external pressure or impact. 2.
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NOTES REGARDING COMPACT DISC PLAYER REPAIRS 1. Preparations 1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode). These components are sensitive to, and easily affected by, static electricity. If such static electricity is high voltage, components can be damaged, and for that reason components should be handled with care.
ESD PRECAUTIONS Electrostatically Sensitive Devices (ESD) Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated circuits and some field-effect transistors and semiconductor chip components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity.
SERVICE INFORMATION FOR EEPROM POWER ON FLD no disc status Remote control ‘ ’ + Front ‘STOP’ DETECT NEW EEPROM push same timing during 5s (OPTION EDIT SCREEN) NAME OPT 0 FLD ‘OP-0…. OPT 1 OPT 2 OPT 3 OPT 4 Move to appropriate position OPT 5 and make changes...
PROGRAM DOWNLOAD GUIDE 1. AUDIO PROGRAM Download program file name must be RAD125.HEX If security program (Water Wall) is activated on your PC, you must save the file to the usb storage device and disable the security software, then download the file to your set. Caution: When downloading the file, you should neither unplug the usb device, change to the other function, nor power off the device.
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2. CD PROGRAM Download program file name must be HB001_DATE_00.BIN If security program (Water Wall) is activated on your PC, you must save the file to the usb storage device and disable the security software, then download the file to your set. Caution: When downloading the file, you should neither unplug the usb device, change to the other function, nor power off the device.
SPECIFICATIONS • GENERAL Power supply 110 ~ 240 V, 50/60 Hz Power consumption 60 W Net Weight 3.5 kg External dimensions (W x H x D) 202 x 307 x 278 mm Bus Power Supply (USB) DC 5 V 500 mA Operating conditions Temperature 5 °C ~ 35 °C, Operation status: Horizontal...
SECTION 2. EXPLODED VIEWS • CABINET AND MAIN FRAME SECTION (RAD225B) NOTES) THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE. 260L FRONT SMPS CABLE2...
SECTION 3. ELECTRICAL PART AUDIO ELECTRICAL TROUBLESHOOTIHG GUIDE 1. POWER (SMPS) No 3.7 VA Is F901 normal? Replace the F901 (Use the same fuse). Is BD901 normal? Replace BD901. Is TH902 normal? Replace TH902. Is Vcc (10 V ~ 18 V) supplied to Is D904 normal? IC901 Pin7? Check or replace D904.
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No PVDD Is F901 normal? Replace F901 (Use the same fuse). Is BD901 normal? Replace BD901. Is TH902 normal? Replace TH902. Is Vcc (10 V ~ 18 V) supplied to Is D905 normal? IC902 Pin7? Check or replace D905. Is Q910 base "H"? •...
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No 12 V Is Vcc Check or replace D921. (15 V) supplied to Q953 collector? Is the Check the power CTL “H” signal 13 V Supplied to Q953 from µ-COM. base? Check or replace Q953. No 5 V Is Vcc Check or replace D923.
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No VFD Check or replace D925. Is D925 normal? Check or replace ZD951. Is ZD951 normal? Is Q951 normal? Check or replace Q951. Check or replace VFD. 2. µ-COM PART CHECK I µ-COM PART CHECK I Check P-SENS CN105 Refer to SMPS Pin9,10 troubleshooting.
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3. µ-COM PART CHECK II µ-COM PART CHECK II Check if voltage of CN105 Pin10 Refer to SMPS troubleshooting. is 3.7 VA. Check Check if output of both end voltage of D105(MBR0540) is 3.7 V. D105, 102. Check if IC102_Pin49 and Check D102, 105.
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5. FLD DISPLAY CHECK FLD DISPLAY CHECK Check CN104 Pin1,2,3 input Refer to SMPS troubleshooting. voltage. Check if both end voltage of F1,F2 are over 3.4 V VKK : over 26 V. Check CN304 connection and power Check CN304 connection. Pin14,15,16(VKK,FL-,FL+), Pin11(3.7 VA).
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Check Check IC602(PS9850) CD Assy communication data input Refer to CD troubleshooting. Pin4, 5, 6. Pin4, 5, 6 PWM wave. Check Check each line IC602(PS9850) data resistor output. input. Check modulator output Check FL: Pin31(+),30(-) Replace IC602(PS9850). IC602(PS9850). FR: Pin28(+),27(-) other output check.
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7. POWER AMP PART CHECK POWER AMP PART CHECK Check CN105 Pin2: +12 V Refer to SMPS troubleshooting. Pin13,15: 29 V. Check IC700, IC701 Pin30,31,38,39,42,43,50,51 input voltage. Check each IC603 Check each line resistor output voltage. Pin64:+12 V input. Check PWM Modulator input IC700 Pin4,5,10,11 / IC701 Pin4, 5.
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8. TUNER/AUX FUNCTION CHECK FUNCTION CHECK Check IC401 (CS5346) Pin7,8, Check JK401,TU100. 23,24 input. Check IC401 Check IC401 Check CN105 Pin7: +5 V Pin46: +3.3 V (CS5346) Pin9 data Pin9,10: +3.3 V. Pin5: +5 V. output. Check IC401 Check IC401 Check Pin6: High IC801(MLC9800)
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9. TUNER FUNCTION CHECK TUNER FUNCTION CHECK Check tuner Check tuner module voltage module(TU100) (Pin4: +3.3 V). operation. Check IC102 Pin21, 22, 23, 24, 25 data in/output. Check tuner module data. Refer to function check. 3-11...
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CDP TROUBLESHOOTIHG GUIDE 1. CD FUNCTION CD FUNCTION Can the Is Motor_open/close ok? Is load +,- ok? disc insert? (IC301 Pin10,11) Check IC301. Is Motor ok? Check loading motor. (about 12 Ω) Focus/ Check IC301 OPU driving (Focus Disc reading tracking/sled signal (Motor drive IC).
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2. USB FUNCTION USB FUNCTION Plug-in usb device. Display “NO USB”. Check usb_5V. Check CN401. Check usb_D+/D- Display “READ”. Check usb jack (JK501). (R501,R502). Display “NO FILE”. Check IC801(Pin116, 117). Replace IC801. Check usb audio fi le in usb device (MP3, WMA fi...
MODIFIED OR ALTERED WITHOUT PERMISSION IMPLEMENTATION OF THE LATEST SAFETY AND during Play mode. FROM THE LG CORPORATION. ALL COMPONENTS PERFORMANCE IMPROVEMENT CHANGES INTO SHOULD BE REPLACED ONLY WITH TYPES IDENTICAL THE SET IS NOT DELAYED UNTIL THE NEW SERVICE TO THOSE IN THE ORIGINAL CIRCUIT.
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2. MAIN - MICOM CIRCUIT DIAGRAM RAT375 µCOM + AD EBY60808601 Rev 4.1 3-23 3-24...
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3. MAIN - CD DSP & SERVO CIRCUIT DIAGRAM RAT375 CD DSP + SERVO EBY60808601 Rev 4.1 3-25 3-26...