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Internal Use Only Website http://biz.lgservice.com 2.1 ch Wireless Sound Bar SERVICE MANUAL MODEL: LAS454B (LAS454B, S55A3-D) CAUTION BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL. P/NO : AFN77195019 NOVEMBER, 2015...
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CONTENTS SECTION 1 ..GENERAL SECTION 2 ..CABINET & MAIN CHASSIS SECTION 3 ..ELECTRICAL SECTION 4 ..WIRELESS SUBWOOFER PART SECTION 5 ..REPLACEMENT PARTS LIST...
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.
WIRELESS SUBWOOFER CONNECTION LED indicator of wireless subwoofer LED Color Status Yellow-green The connection is trying. (Blink) Yellow-green The connection is completed. The wireless subwoofer is in standby mode or the connection is failed. The power cord of wireless (No display) subwoofer is disconnected.
HIDDEN KEY MODE HIDDEN MODE KEYS USB Mode/ UPDATE Main unit ‘- (Volume)’ + Remote control ‘VOL +’ EEPROM EDIT Main unit ‘- (Volume)’ + Remote control ‘CINEMA’ EEPROM CLEAR (Initialize) Main unit ‘- (Volume)’ + Remote control ‘VOICE’ VERSION CHECK Main unit ‘- (Volume)’...
MCS / EQ HIDDEN KEY GUIDE 1. Version & Option Check ※ Please connect the Display Jig to the main unit. 1) Power on. 2) Press main unit "-" (volume -) key and remote control STANDARD key during 3 seconds. 3) Check MCS version.
- Do format USB Memory to FAT32 File system. - USB : Update fi le exist only in the USB Memory stick. Ex ) LAS454B : E:\PG540_FW_LAS454B_Ver.bin (if USB driver is E:\) E:\EQ_PRG.BIN (if USB driver is E:\) Wireless Tx ...
SPECIFICATIONS • GENERAL Power requirements 120 V ~ 60 Hz Power consumption 27 W Networked standby : 0.5 W (If all network ports are activated.) Dimensions (W x H x D) Approx. 950 mm x 71 mm x 47 mm (37.4 inch x 2.8 inch x 1.9 inch) Net Weight Approx.
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SECTION 2 CABINET & MAIN CHASSIS CONTENTS EXPLODED VIEWS ............................2-3 1. MAIN SET SECTION ..........................2-3 2. WIRELESS SUBWOOFER SECTION ...................... 2-5 3. PACKING ACCESSORY SECTION ......................2-7...
EXPLODED VIEWS 1. MAIN SET SECTION NOTES) THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT A44B SAFETY INFORMATION IN SERVICE LITERATURE. CABLE5 SMPS CABLE3 A44A MAIN FRONT CABLE2 CABLE1 CABLE4 WIRELESS...
2. WIRELESS SUBWOOFER SECTION 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. A900 A900W CN901 A47W SMPS A49W A54W A45W WIRELESS 300W...
3. PACKING ACCESSORY SECTION 801 Owner’s manual 806 Optical cable 900 Remote control 808 Batteries (2) 835 Wall bracket 804 Bag 803 Packing, Main 802 Box...
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SECTION 3 ELECTRICAL CONTENTS ONE POINT REPAIR GUIDE ..........................3-2 1. NO POWER PROBLEM (PVDD) ......................3-2 2. POWER ON ERROR ..........................3-3 3. NO SOUND (PORTABLE FUNCTION) ....................3-4 4. NO WIRELESS ............................3-5 5. NO BLUETOOTH ............................ 3-6 6.
ONE POINT REPAIR GUIDE 1. NO POWER PROBLEM (PVDD) No power problem occurs when you power on the unit. 1-1. Solution Replace SMPS board. 1-2. How to troubleshoot (Countermeasure) 1) Check the PVDD voltage 24 V at pin4, 5, 6. When you check the no power at this point, then replace SMPS board.
ONE POINT REPAIR GUIDE 2. POWER ON ERROR No display or Not working. 2-1. IC603 1) Check 12 VA at L604. 2) If 12 VA is not checked at the point, then find 24 V at pin7 of IC603. 3) 1), 2) is NG. Replace IC603. IC603 pin7 IC603 pin7 L604...
ONE POINT REPAIR GUIDE 3. NO SOUND (PORTABLE FUNCTION) 3-1. Solution Replace IC508 or portable jack (JK502). 3-2. How to troubleshoot (Countermeasure) 1) Please check the soldering status of JK502. 2) Please check L501, L502 (POR_L, POR_R signal) of portable jack (JK502). If you can’t find input signal, replace JK502.
ONE POINT REPAIR GUIDE 4. NO WIRELESS 4-1. Solution Replace IC505 on MAIN board.(No 3.3 V) 4-2. How to troubleshoot (Countermeasure) 1) Please check externally status of Wireless board to board connection on your eyes. (at CN506 and Wireless module) 2) Please check 3.3 V of WL_3V3 (at L509).
ONE POINT REPAIR GUIDE 5. NO BLUETOOTH 5-1. Solution Replace IC502 on MAIN board.(No 3.3 V) 5-2. How to troubleshoot (Countermeasure) 1) Please check externally status of Bluetooth cable connection on your eyes.(at CN508 and Bluetooth module) 2) Please check 3.3 V of 3.3VA (at L504). If 3.3 V is OK at L504, please check BT_SDA, BT_SCL, BT_RST (pin53, 51, 25) of IC502 and BT_RX, BT_TX (pin29, 27).
ONE POINT REPAIR GUIDE 6. NO SOUND (OPTICAL) 6-1. Solution Replace IC507 on MAIN board. 6-2. How to troubleshoot (Countermeasure) 1) Please check 3.3 V of 3.3VA at L503. If you can check 3.3 V, please confirm OPT_DET signal (R5R8) in MAIN board when optical mode. 2) In spite of process 1), set has abnormal output, then replace IC507.
ONE POINT REPAIR GUIDE 7. D(DC) PROTECTION 7-1. Solution Replace IC703 (AMP IC) on MAIN board. 7-2. How to troubleshoot (Countermeasure) 1) After MAIN SET power off, check Red LED blink at intervals of 1 sec. (D Protection or S Protection) 2) Turn MAIN SET power on again.
ONE POINT REPAIR GUIDE 8. S(SHUT DOWN) PROTECTION 8-1. Solution Replace IC703 (AMP IC) on MAIN board. 8-2. How to troubleshoot (Countermeasure) 1) After MAIN SET power off, check Red LED blink at intervals of 1 sec. (D Protection or S Protection) 2) Turn MAIN SET power on again.
ONE POINT REPAIR GUIDE 9. B(BURNT) PROTECTION 9-1. Solution Replace IC703 (AMP IC) on MAIN board. 9-2. How to troubleshoot (Countermeasure) 1) After MAIN SET power off, check Red LED blink at intervals of 0.5 sec. (B Protection) 2) Turn MAIN SET power on again. 3) Check voltage 3.3 V of AMP_PROTECT signal (pin2 of Q701).
5. REMOTE CONTROL FIG 5-1. Input Voltage 15 16 FIG 5-2. Low Timing Item Measured Spec. IR Receiver Spec: Input Level 3.3 V 2.7 ~ 5.5 V “ Low” Timing 4.4 ms 3.6 ms ~ 5.04 ms “ High” Timing 4.48 ms 4.08 ms ~ 5.04 ms FIG 5-3.
WIRING DIAGRAM Tact Key Front PCB RCU receiver SMD 10pin Main To Front (FFC) Optical DIP 2pin (Power Cord) DIP 6pin B to B (Main to SMPS) Portable SMPS PCB SMD 2pin SMD 3pin Main PCB Audio L Audio R SMD 10pin SMD 26pin Main To BT...
DESIGN BE MODIFIED OR ALTERED WITHOUT DIFFER FROM THE ACTUAL CIRCUIT USED. THIS 2. Voltages are DC-measured with a digital voltmeter PERMISSION FROM THE LG CORPORATION. ALL WAY, IMPLEMENTATION OF THE LATEST SAFETY during Play mode. COMPONENTS SHOULD BE REPLACED ONLY WITH...
2. CONNECTORS Mearsured Voltage Part Designator Description Specifi cation Pin Number Voltage Spec Remark (Main) 12 V 11.87 V 04-6232-008-010-000 8P 1.00MM FFC/FPC CN504 Connector,FFC/FPC/PIC STRAIGHT TOP SMD TP NON_LOCKING - KY- 5.13 V DISPLAY JIG OCERA CORPORATION 3.3 V 3.32 V 04-6495-626-000-846+ 26P 0.50MM FFC ANGLE CN506...
PRINTED CIRCUIT BOARD DIAGRAMS 1. SMPS P. C. BOARD DIAGRAM (TOP VIEW) NOTE) Warning Parts that are critical with respect to risk of fire or electrical shock. (BOTTOM VIEW) 3-43 3-44...
3. FRONT P. C. BOARD DIAGRAM (TOP VIEW) (BOTTOM VIEW) 3-47 3-48...
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SECTION 4 WIRELESS SUBWOOFER PART CONTENTS ONE POINT REPAIR GUIDE ..........................4-2 1. NO POWER PROBLEM (PVDD) ......................4-2 2. POWER ON ERROR ..........................4-3 3. POWER ON ERROR ..........................4-4 4. WIRELESS CONNECTION ........................4-5 WAVEFORMS OF MAJOR CHECK POINT ...................... 4-6 1.
ONE POINT REPAIR GUIDE 1. NO POWER PROBLEM (PVDD) No power problem occurs when you power on the unit 1-1. Solution If you check these points and find PVDD voltage is not checked, replace woofer SMPS board. 1-2. Service hint (Any picture / Remark) PVDD PVDD pin3, 4, 5, 6 at WCN601...
ONE POINT REPAIR GUIDE 2. POWER ON ERROR Fundamental power check points 2-1. 12 V 1) Check 12 V at WL604 nearby WL603 coil. 2) If 12 V is not checked at the point, then find PVDD at pin7 of WIC606. 3) 1), 2) is NG ...
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ONE POINT REPAIR GUIDE 3. POWER ON ERROR MAIN SoC IC supply voltage check points 3-1. 3.3 VA 1) Check 3.3 VA at WCA603 and WL627. 2) Check 3.3V_PWM at pin5 of WIC605. 3) Check 3.3 VA at pin7, 8 of WIC603. 4) Check 3.3V_PWM at WL615 nearby WIC601.
DIFFER FROM THE ACTUAL CIRCUIT USED. THIS 2. Voltages are DC-measured with a digital voltmeter 1. WOOFER SMPS CIRCUIT DIAGRAM PERMISSION FROM THE LG CORPORATION. ALL WAY, IMPLEMENTATION OF THE LATEST SAFETY during Play mode. COMPONENTS SHOULD BE REPLACED ONLY WITH...
PRINTED CIRCUIT BOARD DIAGRAMS 1. WOOFER SMPS P. C. BOARD (TOP VIEW) (BOTTOM VIEW) NOTE) Warning Parts that are critical with respect to risk of fire or electrical shock. 4-21 4-22...