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Internal Use Only Website http://biz.lgservice.com Mini Hi-Fi System SERVICE MANUAL MODEL: CM9520 (CM9520, CMS9520F/S/W) CAUTION BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL. FEBRUARY...
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CONTENTS SECTION 1 ..GENERAL SECTION 2 ..CABINET & MAIN CHASSIS SECTION 3 ..ELECTRICAL SECTION 4 ..REPLACEMENT PARTS LIST...
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. Storage in conductive bag Drop 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.
HIDDEN KEY MODE Push both Front key and RCU key to activate it for 5 seconds. 1. Disc Lock On/Off (CD Function Only Active) Front Key : STOP RCU Key : STOP 2. Check Version and Option code Front Key : STOP RCU Key : PLAY/PAUSE You can change [Audio MCU Version <->...
SERVICE INFORMATION FOR EEPROM POWER ON FLD no disc status Remote control ‘ ’ + Front ‘STOP’ DETECT NEW EEPROM push at a time for 5 seconds (OPTION EDIT SCREEN) NAME FLD ‘OP-0…. Move to appropriate position and make changes with remote control. /■...
PROGRAM DOWNLOAD GUIDE 1. AUDIO PROGRAM Download program file name must be CM9520_YYMMDDX.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.
2. CD PROGRAM Download program file name must be HE003_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.
3. BEAT BOX PROGRAM Download program file name must be BEAT_BIN_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.
4. EQ PROGRAM Download program file name must be EQ_PRG.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 requirements Refer to main label Power consumption Refer to main label Dimensions (W x H x D) 285 x 395 x 381 Net Weight (Approx.) 6,2 kg Operating temperature 5 °C to 35 °C (41 °F to 95 °F) Operating humidity 5 % to 90 % Bus Power Supply...
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SECTION 2 CABINET & MAIN CHASSIS CONTENTS DISASSEMBLY AND ASSEMBLY FOR MECHANISM DECK (DVM-H1803) ......2-2 1. ORDER OF DISASSEMBLY FOR MECHANISM DECK ................2-2 2. ORDER OF ASSEMBLY FOR MECHANISM DECK ................2-6 EXPLODED VIEWS ........................... 2-11 1. CABINET AND MAIN FRAME SECTION (CM9520) ................2-11 2.
DISASSEMBLY AND ASSEMBLY FOR MECHANISM DECK (DVM-H1803) 1. ORDER OF DISASSEMBLY FOR MECHANISM DECK 1) Disassemble the Cover Guide Disc. Figure 1 2) Disassemble the Loading FFC from the Main PCB Assy. Turn the Gear in OPEN direction as shown in Figure 2 to take out the Tray Loading Assy in 3 direction.
ORDER OF DISASSEMBLY FOR MECHANISM DECK 4) Loosen the screw to pull up and disassemble the Tray Disc. Figure 4 5) Loosen the screw to pull up and disassemble the Gear Tray CAM. Figure 5 6) Disassemble the Gear Tray, Tray Motor Assy and Loading PCB Assy from the Tray Loading.
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ORDER OF DISASSEMBLY FOR MECHANISM DECK Figure 7 7) Disassemble the FFC Cable from the Base Main. Disassemble the Base Sled Assy from the Base Main by referring to Figure. Figure 9 9) Push the Guide UD in direction 1 to disassemble it from the Base Main.
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ORDER OF DISASSEMBLY FOR MECHANISM DECK 10) Use a solder to remove the Motor Jump Wire from the Main PCB Assy and then disassemble the FFC Cable. Loosen the screw to disassemble the Main PCB Assy. Figure 10...
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2. ORDER OF ASSEMBLY FOR MECHANISM DECK 1) Assemble the Loading Motor Assy to the Base Main. (When assembling the Motor Assy, use the hook on the surface of the Base Main to preassemble, and then tighten the screws.) Figure 1 2) Set the Guide UD on the Base Main.
ORDER OF ASSEMBLY FOR MECHANISM DECK 3) Set the Gear Loading 1 and Gear Pulley 2 on the Base Main. Hang the belt between the Gear Pulley and Motor Pul- ley. Assemble the Clamp Disc, Clamp Magnet and Cover Plate to the Base Main. Figure 3 4) After setting the Gear Main 2, Gear Pu Up 3 and Gear Pu Down 4 on the Base Main, tighten the screws.
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ORDER OF ASSEMBLY FOR MECHANISM DECK Figure 5 Figure 6 5) After setting the Main PCB Assy on the Base Main, 6) Set the Base Sled Assy on the Base Main. tighten the screw. (When setting the part, assemble with the CAM part of (Set the part accurately on the hook) the Guide UD inserted in two locations of the Boss of Solder the Motor Jump Wire on the PCB set on the...
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ORDER OF ASSEMBLY FOR MECHANISM DECK Figure 7 Figure 8 7) After setting the Gear Tray, Tray Motor Assy and 8) Assemble the Gear Tray CAM on the Tray Loading Loading PCB Assy on the Tray Loading, tighten the and set the Tray Disc. screw.
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ORDER OF ASSEMBLY FOR MECHANISM DECK Figure 9 Figure 10 9) Assemble the Tray Loading Assy on the Base Main 10) After setting the Cover Guide Disc, tighten the Assy as shown in the Figure. screw. After assembling, insert the Loading FFC to the 5 Pin Wafer of Main PCB Assy.
EXPLODED VIEWS NOTES) THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED 1. CABINET AND MAIN FRAME SECTION (CM9520) TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE. CABLE1 CABLE6 CABLE5 iPod SMPS CABLE4 CABLE7 MAIN VOLUME...
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SECTION 3 ELECTRICAL CONTENTS TRAINING MASTER ........................... 3-2 1. NO SOUND FROM SPEAKERS ......................3-2 2. NO SOUND IN AUX FUNCTION ......................3-3 3. NO SOUND IN PORT. IN FUNCTION ....................3-4 4. NO SOUND IN IPOD FUNCTION ......................3-5 5.
TRAINING MASTER 1. NO SOUND FROM SPEAKERS Make sure to connect the cables to each specified Are the speaker cables connected correctly connector tightly on the unit. between the speaker terminals on the unit Connect the woofer cables to the WOOF SYSTEM and the speakers? connectors on the rear panel.
TRAINING MASTER 2. NO SOUND IN AUX FUNCTION Make sure to connect some cables Does the customer select correctly between the AUX IN jacks of the unit the AUX function he or her wants to listen to? and the Audio output jacks of a external Audio device. After pressing the FUNCTION, Make sure to select the AUX IN function is “AUX”...
TRAINING MASTER 3. NO SOUND IN PORT. IN FUNCTION Make sure to connect a cable Does the customer select correctly between the PORT. IN jack of the unit and the Audio the PORT. IN function he or her wants to listen to? output jack of a portable device like a MP3 player.
TRAINING MASTER 4. NO SOUND IN IPOD FUNCTION Does the customer select correctly Make sure to put a iPod or a iPhone the iPod function he or she wants to listen to? on the docking system on the top of the unit. Make sure that The unit supports the models as follows/iPod nano 1 G, 2 G, 3 G, 4 G, 5 G, 6 G/ Does the customer use the compatible iPod?
TRAINING MASTER 5. NO SOUND IN AM/FM FUNCTION Does the customer select correctly Make sure to connect AM/FM antennas the AM/FM function he or she wants to listen to? on the rear panel of the unit. Make sure to select AM or FM function Is “AM or FM”...
TRAINING MASTER 6. NO SOUND IN CD FUNCTION Does the customer select correctly Make sure to put on a CD disc on the tray. the CD function he or she wants to listen to? Is a CD disc put on the tray correctly? Make sure to insert the CD disc upside down.
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TRAINING MASTER TRAINING MASTER Maker sure to connect the cables Are the speaker cables connected correctly to each specified connector tightly on the unit. between the speaker terminals on the unit Connect the woofer cables to the WOOF SYSTEM and the speakers? connectors on the rear panel.
TRAINING MASTER 7. NO SOUND IN USB FUNCTION Does the customer select correctly Make sure to insert a USB into the USB ports. the USB function he or she wants to listen to? Make sure to select the USB function Is “USB”...
TRAINING MASTER The sound is output from the speakers. Sound OK 8. NO POWER Is the power cord plugged Make sure to plug the power cord of the unit into a electrical outlet? into a electrical outlet. If the customer can not see the red light Does the Standby LED light on the front panel, the SMPS might have any problem.
ONE POINT REPAIR GUIDE 1. NO POWER If the unit doesn’t work by no power problem, repair the set according to the following guide. 1-1. FUSE & BRIDGE DIODE 1-1-1. Solution Please check and replace F901, BD901, TH901, TH902 on SMPS board. 1-1-2.
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ONE POINT REPAIR GUIDE NO POWER If the unit doesn’t work by no power problem, repair the set according to the following guide. 1-2. D951 / D952, ZD951 1-2-1. Solution Please check and replace D951 / D952, ZD951 on SMPS board. 1-2-2.
ONE POINT REPAIR GUIDE 2. NO BOOTING WHEN POWER ON THE SET The set doesn’t work when press the power button on the front board or the remote control. 2-1. FLASH MEMORY (IC101) 2-1-1. Solution Please check and replace IC101 on MAIN board. 2-1-2.
ONE POINT REPAIR GUIDE 3. VFD IS NOT DISPLAYED WHEN POWER ON THE SET When power on the set, any icons or characters on VFD are not displayed. 3-1. VFD 3-1-1. Solution Please check and replace DIG301 on FRONT board. 3-1-2.
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ONE POINT REPAIR GUIDE 4. 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. 4-1.
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. 4-2.
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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. 4-3.
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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. 4-4.
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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. 4-5.
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ONE POINT REPAIR GUIDE 5. NO OPERATION OF MD When no sound output in the CD function, you can not listen to music reading data from a CD disc if the servo motors in MD don’t work. This step is for checking the SPINDLE MOTOR among them.
ONE POINT REPAIR GUIDE NO OPERATION OF MD When no sound output in the CD function, you can not listen to music reading data from a CD disc if the servo motors in MD don’t work. This step is for checking the SLED MOTOR among them.
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ONE POINT REPAIR GUIDE NO OPERATION OF MD When no sound output in the CD function, you can not listen to music reading data from a CD disc if the servo motors in MD don’t work. This step is for checking the TRAY MOTOR among them.
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ONE POINT REPAIR GUIDE NO OPERATION OF MD When no sound output in the CD function, you can not listen to music reading data from a CD disc if the servo motors in MD don’t work. This step is for checking the TRAY OPEN/CLOSE MOTOR among them.
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ONE POINT REPAIR GUIDE NO OPERATION OF MD When no sound output in the CD function, you can not listen to music reading data from a CD disc if the pickup module in MD doesn’t work. This step is for checking the LASER TRACKING ACTUATOR.
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ONE POINT REPAIR GUIDE NO OPERATION OF MD When no sound output in the CD function, you can not listen to music reading data from a CD disc if the pickup module in MD doesn’t work. This step is for checking the LASER FOCUSING ACTUATOR.
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ONE POINT REPAIR GUIDE 6. NO SOUND There is no sound output in the CD FUNCTION, repair the set according to the follow- ing guide. 6-1. IN THE CD FUNCTION 6-1-1. Solution Please check and replace IC501, IC602, IC801 on MAIN board. 6-1-2.
ONE POINT REPAIR GUIDE NO SOUND There is no sound output in the USB FUNCTION, repair the set according to the fol- lowing guide. 6-2-1. IN THE USB FUNCTION 6-2-1-1. Solution Please check and replace IC501, IC504 on MAIN board & IC3U01 on USB board. 6-2-1-2.
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ONE POINT REPAIR GUIDE NO SOUND There is no sound output in the USB FUNCTION, repair the set according to the fol- lowing guide. 6-2-2. IN THE USB FUNCTION 6-2-2-1. Solution Please check and replace IC501, IC504 on MAIN board & IC3U01 on USB board. 6-2-2-2.
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ONE POINT REPAIR GUIDE NO SOUND There is no sound output by DIGITAL AUDIO AMP DAMAGE, repair the set according to the following guide. 6-3. BY DIGITAL AUDIO AMP DAMAGE (IN ALL FUNCTIONS) 6-3-1. Solution Please check and replace IC701, IC702, IC703 on MAIN board. 6-3-2.
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ONE POINT REPAIR GUIDE NO SOUND There is no sound output in the AUX FUNCTION, repair the set according to the fol- lowing guide. 6-4. IN THE AUX FUNCTION 6-4-1. Solution Please check and replace IC202 on MAIN board. 6-4-2. How to troubleshoot (Countermeasure) 1) Check AUX_L/R signals to IC202 (Pin7, 8).
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ONE POINT REPAIR GUIDE NO SOUND There is no sound output in the IPOD FUNCTION, repair the set according to the fol- lowing guide. 6-5. IN THE IPOD FUNCTION 6-5-1. Solution Please check and replace IC201, IC202, IC203 on MAIN board. 6-5-2.
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ONE POINT REPAIR GUIDE NO SOUND There is no sound output in the PORT. IN FUNCTION, repair the set according to the following guide. 6-6. IN THE PORT. IN FUNCTION 6-6-1. Solution Please check and replace IC202 on MAIN board. 6-6-2.
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ONE POINT REPAIR GUIDE NO SOUND There is no sound output in the TUNER FUNCTION, repair the set according to the following guide. 6-7. IN THE TUNER FUNCTION 6-7-1. Solution Please check and replace IC202, TU101 on MAIN board. 6-7-2. How to troubleshoot (Countermeasure) 1) Check if TUNER_LR is entered from Pin1 &...
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ONE POINT REPAIR GUIDE NO SOUND There is no sound output in the MIC IN FUNCTION, repair the set according to the following guide. 6-8. IN THE MIC IN FUNCTION 5-8-1. Solution Please check and replace IC603, IC605 on MAIN board. 6-8-2.
ELECTRICAL TROUBLESHOOTING GUIDE 1. POWER SUPPLY ON SMPS BOARD No output 5.7 VA Replace F901 (same fuse). F901 normal? Replace BD901. BD901 normal? D904 normal? Replace D904. Replace D933, D937. D933, D937 normal? Power line of MAIN PCB is short. 3-35...
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ELECTRICAL TROUBLESHOOTING GUIDE No output 12 V F901 normal? Replace F901 (same fuse). Replace BD901. BD901 normal? Replace D904. D904 normal? Replace D934, D935. D934, D935 normal? Replace IC931. IC931 normal? Power Line of Main PCB is short. 3-36...
ELECTRICAL TROUBLESHOOTING GUIDE 2. SYSTEM PART Power on. CN301 “HELLO” cable connection Display on FLD Check FFC cable (17P). CN301 Pin15, 16, 17 power Check SMPS board. CN301 Pin8, 9, 10 data signal Check MAIN board. Q301, 303, 304 Replace DIG301. grid voltage OK? Volume LED CN3V01 Pin30...
ELECTRICAL TROUBLESHOOTING GUIDE 3. NO AUDIO PART CD FUNCTION Is motor_open/ close OK? LOAD +- OK? disc insert? (IC408 Pin9,10) Check IC501. Is motor impedance Check Loading motor. about 12 Ω? Check IC408. Focusing/ OPU driving Tracking/ Sled Signal Disc reading OK? (Focusing &...
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ELECTRICAL TROUBLESHOOTING GUIDE USB play IC501 Check IC501. Pin16,18 USB_HUB_D output signal OK? IC3U01 When insert USB power +5 VU Replace IC3U01. USB,IC504 Pin1,2,3,4 USB_D signal OK? IC202 Pin7,8 AUX input signal Check audio cable. IC202 Check IC501. Pin42,43,44 I2S input signal IC202 Replace IC202.
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ELECTRICAL TROUBLESHOOTING GUIDE POT. IN IC202 Pin21,22 POT. IN input signal Check MIC board. IC202 Check IC501. Pin42,43,44 I2S input signal IC202 Replace IC202. Pin41 ADC data output signal iPod IC203 IC202 Pin4 USB_VBUS 5 V Pin26,27 iPod input signal Check USB_VBUS of IC203.
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ELECTRICAL TROUBLESHOOTING GUIDE TUNER TU101 IC202 TUNER_L/R output Pin23,24 TUNER_L/R input Check +3.3 V of TU101. signal OK? signal OK? IC202 Pin42,43,44 I2S input Check IC501. signal OK? IC202 Pin41 ADC data output Replace IC202. signal OK? 3-43...
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ELECTRICAL TROUBLESHOOTING GUIDE IC501 Replace IC501. Pin4, 5, 6 I2S data output signal OK? IC507 Check IC507. Pin2, 17 DAC_BCK/LRCK input signal OK? IC507 Replace IC507. Pin7,14 BEAT_LRCK/BCK output signal OK? IC501 Check IC501. Pin6 BEAT_DAC_DATA output signal OK? IC801 Check IC501.
BLOCK DIAGRAMS 1. SMPS BLOCK DIAGRAM MAIN STR-A6053 for Main Power TRANS Rectifier Circuit (Bridge, CAPACITOR) Filter Section (Varistor, Resistor, Line Filter Snubber Thermistor) Digital TRANS AMP Power & Power MAIN NCP1252 Control IC & 3-55 3-56...
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.
CIRCUIT VOLTAGE CHART 1. ICs IC Sym IC Name / Type Vcc/Vdd IC Sym IC Name / Type Vcc/Vdd IC Sym IC Name / Type Vcc/Vdd IC Sym IC Name / Type Vcc/Vdd LC87F5NC8A Spec: Spec: 74AHC244FT Spec: IC408 S3053 Spec: IC101 (SANYO)
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MEMO 2. CAPACITORS Value Value Voltage Measured Voltage Measured Location Capacitor Location Capacitor Spec voltage Spec voltage (uF) (uF) <MAIN> C244 100uF 5.61 C122 100uF 3.31 C231 47uF 5.08 C151 47uF 3.43 C236 10uF 5.19 C124 1000uF 3.41 <VFD> C601 100uF 3.32 C243...