LCD Troubleshooting, LCD display OK? Yes | LG Electronics LG-C320

4. TROUBLE SHOOTING

4.8 LCD Troubleshooting

LCD control signals are generated by QSC6270.

The signal path is : QSC6270 Æ CN102 Æ LCD Module

START



Press END key
			No

Key LED is on?
Key LED is on?

Yes

Disconnect and reconnect

The LCD connector

(Slide PCB CN102,CN101)

LCD display OK?	Yes

No

Change the FPCB

Move to KEY LED Troubleshooting

END

LCD display OK?

No

Yes

END

Change SUB PCB

LCD display OK?

No

Yes

END

Change the Main Board

Copyright © 2010 LG Electronics. Inc. All right reserved.	- 63 -	LGE Internal Use Only
Only for training and service purposes

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LG Electronics LG-C320 LCD Troubleshooting, Change the Fpcb Move to KEY LED Troubleshooting, LCD display OK? Yes

Contents

LG-C320 Internal Use Only Table Of Contents LGE Internal Use Only Purpose Regulatory Information Electrostatic Sensitive Devices PicturesInterference and Attenuation Abbreviations PGA PAMPCB PLL Product Name Main Parts GSM SolutionFeature Comment Supporting Standard HW Features Cdrom Music PlayerMP3/AAC/AAC+/WMA Stereo Headset Yes Data Cable Flash External Memory SW Features ENS MMSEons Cphs 2M FF GSM transceiver specification Specification HW Spec C320 Figures QSC62703G disable Base band block General Description Processor 1 Processors and bus architecture Memory support and LCD interface EBI2 QSC6270 3G disable Qvga Main QSC6270 Connectivity QSC6270 3G disable has 78 configurable I/O pins GPIOs Internal base band functions Enhanced GPS position location using gpsOne with RGR6240 ICAir interfaces JTAG/ETM Multimedia Camera interface and video front-end 7.2.1 MDP-to-LCD interface functional block diagram Mobile display processor 7.2.2 The LCD interface of C320 Hkadc Uart9 USB QSC6270HKADC Block diagram Valid external supply attachment and removal detection Power managementInput power management Output voltage regulation 2 Voltage regulator summary –”—“Œ›Œ‹ Charging controlˆ™Ž•Ž YlTŠˆ™Ž•Ž Technical Brief SUB System KEY PAD External memory interface EBI1 FeaturesEBI2 Features Sdram Camera Interface 2M Camera 3.1 2M Camera Technical Brief LCD Module LQ024Q3UX01 Sharp General Description Input Signal and Power Pin Description Input Pin PIN Description Technical Brief Audio Signal Processing & Interface 41 Block diagram of RF part General Description RF Part High-band Low-bandGSM 850 869 to 894 MHz and GSM 900 925 to 960 MHz 1 QSC GSM receiver signal paths functional diagram GSM Transmitter 1 Block diagram of FEM 1 Control table of FEM 1 D5008 FL101 FEM 2 Block diagram of GSM PAM Bluetooth BCM2070 Shows the Bluetooth system architecture in the LG-C320 Bluetooth ConnectionGPIO with QSC6270 ESC6270 FM Receiver TEA5991FM TEA5991 2 pin description Start Power on TroubleshootingWhen Power key press? Yes Than 3.20V? Yes TP1 Charger Troubleshooting Flow Charger TroubleshootingConnection OK? Change I/O connector Yes Yes Change TA Is it charging properly? TP1 FL401 USB Troubleshooting USB Troubleshooting Flow TP3 Yes Change the SIM card Work well ? Usim Detect TroubleshootingRe-insert the SIM card Work well ? Check J301 TP1 TP2 TP3 Camera TroubleshootingTP4 TP4 TP3 TP1 TP2 CAM70MHz Pclk CAM24MHz Mclk Key press +VPWR is above 3.2V? Yes Main side view LED TroubleshootingCheck battery Change QSC6270 Change LED Yes LED on ? Slide Key side view LED Troubleshooting SUB KEY B/L LCD display OK? Yes LCD TroubleshootingChange the Fpcb Move to KEY LED Troubleshooting Change SUB PCB LCD display OK? Yes Slide Side view placement Above 3.0V or Linmotm Vibrator TroubleshootingVibrator is operate when DC motor driver is enabled Fsubfpcb to Main PCB ConnectorCN101 Main to Fsubfpcb ConnectorCN803 Receiver Path Main to Slide Fpcb ConnectorCN801 TP1 TP4Receiver PAD=CN101 TP3FB102 TP3FB101 TP1C506, C507? Change the IC501 TP3FB505 TP3FB504 TP2R505 TP2R504 TP1C507 TP1C506 Speaker/Speaker Phone path Audio Sub TP1C509 TP1C508 SystemIC501 TP2FB507 TP2FB508 TP3 TP4 TP5CN102=Speaker Pad MICBIASTP1C526 Main microphoneMake a call Work well? Mainmicp TP2FB503? Yes Headset microphoneInsert Headset & Make a call TP3C263? Yes Hsgnd RF Component U201 X202 FL101 SW101 U101 RF Path GSM path Trouble Shooting of GSM Part GSM850/GSM900/1800/1900 DCS1800 CH PCS1900 CH GSM850 CH Setup Test Equipnment Cell power = -74dbmEgsm CH Check Rx Part Tx Part Checking Front-End Module Block Check U201 Replace FL101 TP1 TP2 Checking GSM Rx part GSM Rx is OK DCS/PCS = 17.3 Gpam Logic Control Trouble Shooting RF component BT Main board bottom Reference Description Checking Bluetooth BlockBluetooth RF components ANT Bluetooth Signal Path Bluetooth Signal Path Main board bottom TP1 VREGMSMP2.6V TP2 VREGMSME1.8V TP3 Bluetooth Trouble shootingTP# TP4 Btantout ConnectivityANTPAD Class BT main clk 26MHz Reference Description U701 TEA5991FM module FM Signal PathChecking FM Radio Block FM Trouble shooting TP1 VREGMSMP2.6V TP2 VREGMSME1.8V TP3 Fmantin TP4 Fmoutaudio signalTP description Download LG-C320 LG-C320 LGE Internal Use Only 101 102 103 104 105 106 107 108 LG-C320 LG-C320 109 LG-C320 LG-C320 110 LG-C20 111 Block Diagram 112 113 Usbvbus 114 Vbat 115 Memory 116 117 118 119 ESC6270 WM9093 120 QSC6270 121 122 Circuit Diagram 123 2-1ESCESC6270 124 NET Conn MCP2-12G1G DDRx16hynix 126 3-2 127 2-1 128 6CH+4LDO,PWM 129 ConnectivityANTPAD 130 1-1 131 1-3push1.50T 132 KEY PCB 133 Slide Fpcb 134 Module Fpcb 135 136 137 QSC6270 3G disableٛ- U200 bottom viewBGA Pin Map H8BCS0SI0BAR-46M MCP,NAND U300 EUSY0347506 138 BCM2070B2KUBXG bluetooth U700 EUSY0418701 139 140 141 WM9093 Ultra Low Power Audio Subsystem- IC500 EUSY0403901Bump CSP package Top View TEA5991FM Tuner- U701 EUSY0385901 142 LD801/802 Main Key LED Can not use LED 143 U101 GSM PAM IC401 MuicFL101 FEM C320KEYSPEY006820110TOP 145 CN102 LCD Connector Can not use LCD Display, LCD Backlight 146 C320FSLIDESPCY024690110TOP 147 CN101 Fpcb Conn Can not use SD-card, Vibrator, Speaker 148 Usage of Tachyon for RF Calibration and Test Preparation work for setting RF cable lossProcedure 149 150 Basic Setting of Tachyon for RF Calibration & TestSystem Option Setting Contents Log of RF Calibration and Test Phone Test Mode 152 Order 153 154 155 156 Exploded View & Replacement Part List 157 158 159 160 161 162 Hankook Molex 163LGC320.ABOOWA Flexible Mobitech Corporation 164 RESIN,PC 165LG-C320 Boowa Main TP TDK Korea Cooperation Kyocera Corp 166TP TDK Corporation Rohm 167 168 AUK Corp ESM R/TP 3P KEC Corporaition 169FET H8BCS0SI0BAR-46M NAND/2G SDRAM/1G 1.7VTO1.9V 170IC,MCP,NAND 171 SPM0410LR5H-QB SPM0410LR5H-QB,UNIT,42 QCT Skyworks Solutions INC172 Printed Circuit Board Corp 173 ECZH0001217 Ceratech Corporation 174Microelectronics PLC Accessory 175