Keypad back light trouble | LG Electronics KS360 instruction

5. Trouble shooting

5.10 Keypad back light trouble

Check Points

-Signal path is connected well

-TR is working properly

QWERTY_KEY BACKLIGHT

VBAT

		R310
LEWWS44-E	LD300	47
		R311
LEWWS44-E	LD301	47
		R312
LEWWS44-E	LD302	47

TP1

QWERTY_KEY_BL

VA301

ICVN0505X150FR

MULTI_KEY BACKLIGHT

VBAT

C101

100ohm

100ohm

100ohm

100ohm

100ohm

100ohm

100ohm

1u

R103

LEBB-S14E

R104

LEBB-S14E

R105

R106

LEBB-S14E

R107

LEBB-S14E

R108

LEBB-S14E

R109

LEBB-S14E

LD100

LD101

LD102

LEBBS14E- LD103

LD104

LD105

LD106

R110

TP2

Q100

SUB_KEY_BL

2SC5585

1K

R111

10K

TP1

TP2

C102

1u

LGE Internal Use Only	- 82 -	Copyright © 2008 LG Electronics. Inc. All right reserved.
		Only for training and service purposes

Image 81

LG Electronics KS360 service manual Keypad back light trouble, Signal path is connected well TR is working properly

Contents

Internal Use Only KS360 Revised History Editor Date Issue Contents of Changes Version Kim JulPage Table Of Contents Page Regulatory Information Purpose Pictures Interference and AttenuationElectrostatic Sensitive Devices BER APCCC-CV CLA Opll LGEPAM PCB Feature Comment H/W FeatureANT HR/EFR/FR/AMR Technical specification EgsmGSM900/EGSM Offset from Carrier kHz Description Specification Description Specification DCS1800/PCS1900 Bit Error Ratio BER Class II 2.439% @-102dBmBER Class II 2.439% @-100dBm Rx Level Report accuracy Stmr General Performance DCS1800, PCS1900 RMS EVM Offset from carrierkHz Max. dBm 400 600 200 800 Due to modulation Offset from carrierkHz KS360 series Functional Block Diagram KS360 series Component Block diagram General Description Baseband Processor BBP Introduction Block Description RF Interface External Devices connected to memory interfaceDevice Name Maker Remark Resource Interconnection Description ADC channel Usart InterfaceUART0 Usif Port Function Net Name Description #Keypad Gpio map DIFRESET1GPIO Keyint Cifresetgpio CamrstCIFD7 Cifpclk Campclk Usifrxdmrst Uartbtrx Usiftxdmtsr UartbttxUsifsclk Btvcxoen #I2S1 DAI-PCM I2S1CLK0 Poresetn / SCANOUT2 ResetnFcdprbn TOUT5 Touchint Block Description Power management IC Top level block diagram of the PMU Block of PMB8888 Usage LDO 2V~3.74V 74V~3.64V 64V~3.45V 45V~3.35V Charging Remote Power On Power ON/OFF SIM Circuit SIM interface Micro SD external memory Interface SD mode Pin No Name Type Description Memory Circuit Memory Pin No Pin Name Description LCD Display LCD-ID ResetVCC1 MLED5 Pin LCD connector circuit Keypad Configuration Circuit Keypad Switching & Scanning CLR Touch KEY Technical Brief Qwerty + MultiKeypad Backlight Circuit Keypad back-light illumination Charge-Pump Circuit LCD back light illumination ISP & Camera Circuit ISPImage Signal Processor Jtag & ETM Interface Circuit Jtag & ETM interface connector Audio KS360 series Audio signal flow diagram as following diagram Microphone circuit Audio amplifier Charging IC OVP Charging circuit Bluetooth / FM Radio Circuit Diagram Bluetoothcsr Technical Brief FM Radio Bluetooth / FM Radio Block Diagram 19 18pin Multi Media Interface connector KM380 series MMIPin Function Description Pin Multi port Circuit Diagram 18PIN IO Connector General Description PMB 8888 Function Block Diagram Gold Radio Circuit Diagram Receiver part Receiver Block Diagram of S-GOLDradio Transmitter part RF synthesizer Transmitter Architecture Block Diagram Front End Module control Dcxo Pin Mame Description Power Amplifier ModuleVbatt Gsmin Main PCB Top Main PCB component placement Main PCB bottom Main PCB bottom placement MMI PAD KEY PCB Top Equipment setup Trouble shooting test setup Check Points Power on Trouble TP2 Trouble shooting Charging trouble 2V~3.75V75V~3.64V 3.64V~3.45V 3.45V~3.35V TP1 TP2 LCD display trouble Main To Fpcb Connector Signal is normal on Camera Trouble Connectors combination Fpcb status Start Speaker pin contact Audio amp soldering SUB Pmic soldering Receiver & Speaker trouble TP4 MIC Microphone trouble TP1 Ear-MIc Jack Detection trouble Vibrator trouble Connectors combination Check Vibrator Connector Combination Keypad back light trouble Signal path is connected well TR is working properly Check All of LEDs solder Check Vbat Check Battery Yes Power is working Socket soldering Proper SIM is used SIM & USD troubleSIM Check Points Soldered well? Yes USD Check Points Power is working Socket soldering Card detect is working Check Micro SD card voltage 2V9VMMC Touch Check Points Touch trouble TP4 Dome switch contacts Key coder IC soldering Qwerty Key troubleKey Check Points Waveform of Dcxo Domeswitch Main PCB Bottom Trouble Shooting of Receiver Part Dcxo Checking Dcxo CircuitDcxo Cicuit Dcxo Waveform Checking Mobile SW & FEM Egsm DCS PCS ANTSW1ANTSW2 ANT SW1 ANT SW2 Mobile SW FEM Control Signals See RX Part 1. Checking Dcxo Circuit Trouble Shooting of Transmitter Part Mode Checking Transceiver Output SignalsGsmk 8PSK Transceiver Output Gmsk Transceiver Output 8PSK Txlb Mode Gmsk TP1 Txlb Mode 8PSK TP1 PAM Control Signals Checking PAM Control SignalsMode Palevel Txonpa PAM Mode Operation 100 Gsmk Control Signal 8PSK Control Signal Checking FEM & Mobile SW Mobile SW & FEM Checking Points TX ModeOff FEM TX Control Logic 101 102 TP1ANT SW1 TP2ANT SW2 S/W download setup Download & upgrade setup Preparation103 104 Download program user guide 105 Multi-Download Program SettingModel-Base 106 Circuit Diagram 18PIN IO Connector Hall Effect S/W108 109 Audio AMP SUB System & Signal Distributor Qwerty KEY 110 SIM Connector Camera ConnectorCamera Power Backup Battery 112 Bluetoothcsr 2V62VIO 113 Main To Fpcb Connector Fpcb To Slide Connector Right 114 Main Receiver 115 116 117 BGA IC pin check U102, PMB8888 118 BGA IC pin check U100, K5D1G12ACD-D075 119 BGA IC pin check U303, MAX9877 120 BGA IC pin check M600, BC5FM 121 PCB Layout 122 GSM RX 123 LD100~106 No MultiKey Backlight 124 125 LCD Connector CN100 No Power No Booting No Display 126 Touch Connector CN102 No Touch Sense CN100 Test Equipment Setup Calibration Step127 128 129 Adjust the number of times 130 131 Calibration data will be saved to the following folder 132 Normal Mode Ptest Mode 133 Stand-alone Test 134 Connected 135 Tx Test 136 Rx Test MF Test BB Test 138 139 Exploded View & Replacement Part List 140 Assy Exploded View 141 Replacement Parts Mechanic component 142 Exploded View & Replacement Part List 143 Main component Is ordered by Sbom standard on Gcsc144 145 146 ECCH0000393 147 148 149 150 151 152 153 FILTER,EMI/POWER 154 155 156 157 158 159 160 161