Huawei U8860 Maintenance Manual
Hide thumbs Also See for U8860:

Advertisement

Quick Links

U8860
Maintenance Manual
Issue
1.0
Date
2011-11-14
HUAWEI TECHNOLOGIES CO., LTD.

Advertisement

Table of Contents
loading

Summary of Contents for Huawei U8860

  • Page 1 U8860 Maintenance Manual Issue Date 2011-11-14 HUAWEI TECHNOLOGIES CO., LTD.
  • Page 2 Notice The purchased products, services and features are stipulated by the contract made between Huawei and the customer. All or part of the products, services and features described in this document may not be within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information, and recommendations in this document are provided "AS IS"...
  • Page 3: About This Document

    Maintenance support engineer 2011-11-14 Approved by Date Service representative 2011-11-14 Change History Date Version Change Reason Revised Description Author Chapter 2011-11-12 V1.0 Released the first issue. R&D Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 4: Table Of Contents

    9.2.4 Flash Memory Circuit ........................... 40 9.3 RF Unit ................................41 9.4 Peripheral Circuits ............................44 9.4.1 Display ..............................44 9.4.2 Keypads ..............................46 9.4.3 Vibration ............................... 48 Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 5 10 Solder Points on the PCB and BGA Chip................75 11 Functional Tests......................... 80 11.1 Keys ................................80 11.2 MMI Test ..............................81 11.3 Voice Call Test .............................. 83 Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 6: Product Introduction

    Maintenance Manual 1 Product Introduction Product Introduction 1.1 Appearance 1.2 Specifications Item Descriptions Dimensions (H x W x D) 122 mm x 61.5 mm x 10.9 mm Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 7 GSM 850 MHz/900 MHz: +32.5 dBm (Power Class 4) GSM 1800 MHz/1900 MHz: +29.5 dBm (Power Class 1) EDGE 850 MHz/900 MHz: 26 dBm(+/-3 dBm) EDGE 1800 MHz/1900 MHz: 25 dBm(+/-3 dBm) Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 8 PCS 1900 MHz: better than -102 dBm/200 KHz Operating temperature: –10 °C to 45 °C (without charger) Temperature Storage temperature: –40°C to 70°C Humidity Operating humidity: 5% to 95% RH Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 9: Applicable Scope And Precautions

    This document provides maintenance instructions for technicians at service centers authorized by Huawei. This service manual is confidential and can be accessed by authorized service sites or companies only. Although every effort has been made to ensure the accuracy of the document, errors may still exist.
  • Page 10: Explosive View

    Note: The components listed in the following table are structural parts of the phone, and cannot be used as reference when applying for spare parts. Description Quantity U8860 touch panel protective film U8860 touch panel U8860 receiver decorating items Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright ©...
  • Page 11 U8860 main FPC U8860 receiver U8860 front camera U8860 main PCB U8860 speaker U8860 battery U8860 battery cover U8860 test point protection jacket U8860 screws U8860 cover B assembly U8860 rear camera U8860 LCD shielding film U8860 microphone U8860 LCD module Issue 1.0 (2011-11-14)
  • Page 12: Components On Pcba

    U5002 RF low noise amplifier damage results in (receive diversity) damage power-on failure, TP results in weak failure, motor vibrating W2100MHz signal. failure, speaker soundless, and approach light failure. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 13 - 3.5 mm damage results in low damage results in or noisy transmitted headphone failure. voice. J1901BTB connector and front camera damages result in front camera failure. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 14 BOM Code Description 15040208 Transient voltage suppression diode-6.8 V-11.4 V-75 W-7 D1301, D1601 A-SOT-363 Transient voltage suppression diode-6 V-14 V-10 W-12 15040238 D1501 A-SOD882/0402 Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 15 U203, U3900 Terminal Dedicated IC, Power Management IC of QUALCOMM 39200177 U301 MSM7x30 Series (PM8058) 39110531 DCDC charging control chip-20-Pin WCSP U1001 39110523 LED flash driver IC-QFN16 U1102 Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 16 RF low-noise amplifier-0.5~3 GHz-16.8 dB-0.87-QFN-250 V U6002 12020141 Crystal oscillator-19.2 MHz-7pF-+/-10 ppm-70 ohm-3.2*2.5*0.6 X401 12020125 Crystal oscillator-0.032768 MHz X402 12020162 Crystal oscillator-24.576 MHz-12 pF-+/-30 ppm-100 ohm-3225 X701 Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 17 Varistor—8 V-4 V-30 V-SMT-0405-ESD + EMI component Z1301 13030048 Ceramic filter-2450 MHz-2.9 dB-2.0*1.25*1.05 mm Z4201 13010148 SAW filter-2140 MHz-50 V-00231804 Z5001 40020162 SDRAM-4Gb LPDDR2-333 MHz-32 bit-1.8 V-240 Ball U201_POP Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 18: Software Upgrade

    Step 5 Before the upgrade, NV items backup is performed (if the phone has not been backed up before). Then the phone restarts and the upgrade starts. Step 6 The upgrade progress is displayed on the LCD. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 19: Troubleshooting

    1. Check whether the upgrade file is correct. the phone using the 2. Check whether the upgrade method is correct. microSD card. 3. Check whether the microSD functions properly. 4. Perform the upgrade again. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 20: Maintenance Tools

    Name: soldering iron Usage: to maintain and solder components Name: DC regulated power supply Usage: to supply DC current Name: soldering table Usage: to secure the main PCBA Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 21 Usage: soldering Name: digital multimeter Usage: to measure during repair Name: toolkit Usage: to assemble and disassemble components Name: electric screwdriver Usage: to fasten and remove screws Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 22: Disassembly Procedure

    U8860 Maintenance Manual 7 Disassembly Procedure Disassembly Procedure 2. Start to disassemble the U8860. 1. Ensure that the ESD wrist strap is well grounded U8860 disassembly guide: 1. Remove the battery cover. 2. Remove the battery. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential...
  • Page 23 3. Remove the six screws from cover B. cover A and cover B. 5. Turn over the buckle in the ZIF interface. 6. Carefully take out the FPC cable. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 24 10. Carefully separate the FPC and cover B (Note: 9. Loosen the BTB connector. there is double-sided tape between the FPC and shielding cover, carefully perform the operation to avoid damaging the FPC). Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 25 3. Separate the BTB that the touch panel connects to main FPC, and lever the part of the main FPC that 1. Introduction to the disassembly tools blocks the TP BTB. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 26 4. Put the front cover components into the jig base. The placing direction is as shown in this Figure (See procedure 4-1 and 4-2 for precautions). 4-2. Note: Do not press TP BTB. 5. Fasten the cover. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 27 7-1. Note: Put the sucker in the opposite direction of 8. Slowly suck up the TP and stop sucking until half of the receiver. the TP is sucked up. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 28 10. Unfasten the screw and gently remove the cover. 11-1. Take out the component and remove the TP gently. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 29 During disassembly, place the tweezers against 13. Remove the LCD. The disassembly is completed. the buckle instead of the glass. The LCD must not be distorted. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 30: Assembly Procedure

    U8860 Maintenance Manual 8 Assembly Procedure Assembly Procedure 1. Ensure that the ESD wrist strap is well grounded. 2. Start to assemble the U8860. 4. Install the receiver. 3. Install the speaker. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 31 8. Install the main board. 9. Paste the FPC on the main board and ensure that the 10. Insert the FPC into the ZIF interface. FPC aligns the positioning hole. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 32 11. Clip the buckle of the ZIF interface. 12. Install cover B. 13. Install the six crews in cover B. 14. Install battery. 16. The U8860 is now assembled. 15. Install battery cover. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential...
  • Page 33: Principles And Troubleshooting

    Before repairing a phone, ensure that the failure of the phone is not caused by environmental factors or incorrect functional settings, it is recommended that you restore the phone to its factory defaults. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 34: Block Diagram And Phone Introduction

    According to logic functions, boards are categorized into four sub-systems, including baseband, RF, power supply, and user interfaces. The following table describes modules and units of each sub-system and supported functions. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 35 RF signal of Bluetooth and WLAN, mainly includes BT + WiFi module and its peripheral circuit WiFi interface WiFi chip Uses BCM4329 chip to perform the WiFi function. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 36 The phone provides internal antenna for signal Antenna internal interface transmission and supports WCDMA high and low component, antenna frequency band. U8860-92 phone antennas include protection main antenna, diversity antenna, WiFi/BT antenna, GPS antenna, FM antenna (headphone) Coupler Power coupler Couples part of the output power of WCDMA power amplifier to QTR8615 for power monitoring.
  • Page 37 A 32.768 KHz sleep clock is provided. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 38: Baseband Unit

    − damaged or fall-off. − The main components are cold-soldered; therefore, the system does not operate normally. In this case, the current is less than 100 mA. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 39 Generally, weak current may be caused by any of the two reasons: − Software faults (Upgrading or reloading the software may solve the problem.) − The PM output circuit is short-circuited. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 40 PM voltage output table: Signal Reference Value for the Output Voltage Test Point VREG_L3_1P8/3P3 1.8/3.0V C449 VREG_MSM_USB3V3 3.0V C469 VREG_MSM_USB1V8 1.8V C470 VREG_CAM_2P85 2.85V R4411 VREG_MSM_A2_2V05 2.85V C456 Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 41 The phone has current (greater than 1 mA) when it has been powered off. Excessive current is caused by short circuits. The main reason is ground short circuits of VBAT. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 42: Charging Management Circuits

    9.2.2 Charging Management Circuits Circuit schematic diagram The power supply of MSM8255 supports two external charging modes: charger mode and USB mode. The schematic diagram is shown as follows: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 43 The phone displays an animated icon indicating that it is charging, but actually, the battery is not charged. To troubleshoot charging failure, firstly check whether the battery connector is damaged. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 44: Clock Circuit

    Is the output voltage of the charging Replace U1001. IC 3.7V-4.2V. Replace U301. 9.2.3 Clock Circuit Clock Effect Remarks Supporting master clock for the VCTCXO in 19.2 MHz MSM8255 Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 45: Flash Memory Circuit

    The LPDDR2 is connected to the MSM8255-0 in PoP (Package-on-package) mode. Meanwhile, the MSM8255-0 also can visit the external storage eMMC through a low-speed bus (EBI2), as shown in the following figure. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 46: Rf Unit

    Maintenance procedure for transmission failure in W2100: Firstly, ensure that the SIM card and antenna are installed properly, and then detect the phone according to the following procedure. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 47 In W900, just replace the U3302 detection with U3402 detection. In GSM900 and GSM1800, just replace the U3302 detection with U3502 detection. Maintenance procedure for reception failure in W2100: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 48 Note table 1: TRX_W2100 TRX_W900 GSM900 Rx GSM1800 Rx In W900, just replace the U3404 detection with U3804 detection. In GSM, just replace the U3404 detection with U3304 detection. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 49: Peripheral Circuits

    The MSM8255 employs the MDDI interface to transmit command and data to the LCD. The U8860 uses Toshiba's LCD. The U8860 uses Toshiba's LCD LT040MDT9000. It is a TFT module with a point matrix of 480RGB x 854, supporting MDDI interface. Its features are: ...
  • Page 50 The anode of the backlight LED LED- The cathode of the backlight LED The U8860 adopts 4.02 inches LCD. The backlight adopts six serial LED lights, which are controlled by the backlight LED-driving chip RT9293BGJ6. Troubleshooting process Failure: The phone can be powered on, but its LCD is blank.
  • Page 51: Keypads

    Replace U201. 9.4.2 Keypads The U8860 has seven keys. Four of them are on the touch panel. You can answer a call, hang up a call, view the menu and back the previous operation by touching them. The GPIO_01 Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright ©...
  • Page 52 VPH_PWR. The keypad LEDs are the four LEDs on the LCD. Keypad backlight driver Signal Description Remarks VPH_PWR Power supply Backlight power supply KPD_DRV_N Backlight driver When the level is low, the four backlight LEDs light. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 53: Vibration

    The PM VIB_DRV_N controls the vibrator's driving voltage. The VIB_DRV_N controls the motor vibration by setting high level or low level. When the VIB_DRV_N is in low level, the motor vibrates. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 54: Call Reception

    Failure: After a call is established, no sound can be heard or noises are heard. Solution: For audio fault, check whether the phone is set properly. Generally, the reception faults are caused by earpiece fault or poor earpiece contact. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 55: Call Transmission

    Replace U4001. 9.4.5 Call Transmission Troubleshooting process Failure: No sound is heard by the other party during a call. Solution: Check whether the phone is set properly. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 56 1.8 V? Is the problem solved after the MIC is replaced. Are the components on the circuit that between the MIC and U4001 are damaged or short-circuited? Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 57: Headphone

    R902. The headphone MIC is supplied with power by MIC_BIAS1 (PM8058/HSED_BIAS1), and it is used for headphone answer detection. U8860's headphone is compatible with two line sequences. The iphone's headphone line sequence is compatible by default. Troubleshooting process Failure: Perform the test using a normal headphone, and no sound is heard.
  • Page 58 Are the components on Replace the faulty the circuit that between the MIC components. and U4001 are damaged or short-circuited? Replace U4001. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 59: Sim Card

    Is there signal is input in Is the circuit between MIC2N/MIC2P when speaker? MIC2N/MIC2P and U4001 short-circuited? Re-solder or replace U4001. 9.4.7 SIM Card Circuit schematic diagram Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 60 After the cabling problem is Are the power-supply pin excluded, re- and signal pin normal? solder or replace the U301. Re-solder or replace the U301. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 61: I/O Connector

    Description of the signals in the circuit diagram in this section Signal Description Reference Measurement or Wave Form VEXT_DC Charging current input High level, 5 V USB_DM Digital signal USB_DP Digital signal Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 62: Microsd Card Connector

    SD card through the pin. SDC4_CLK controls SD card data transmission and clock process. The data cable transmits data. Troubleshooting process Failure: The microSD cards cannot be detected or read. Solution: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 63: Camera

    Is the SD card’s VDD Is the power power supply normal? supply circuit short-circuited? Is the data transmission circuit damaged or short-circuited? 9.4.10 Camera Circuit schematic diagram Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 64 I2C bus to control the camera. The camera communication is implemented depending on the MIPI interface. The data is synchronously provided by two CAMMIPI clocks, and is transmitted by data interface. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 65 The function implementation method for the secondary camera is same as that for the primary camera while their data transmission modes are different. Troubleshooting process: Failure: No image can be captured. Solution: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 66: Bt&Wifi

    The ready to receive information sent to the Slave by the Host QTR_BT_UART_RTS The clear to send information sent to the Host by the Slave QTR_BT_UART_TXD Sending signal QTR_BT_UART_RXD Receiving signal QTR_BT_PCM_DIN PCM input QTR_BT_PCM_DOUT PCM output Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 67 After the WiFi function is enabled, the data transmission is controlled by SDC3_CLK and SDC3_CMD, and is performed by the four data control pins. Troubleshooting process Failure: the BT and WiFi functions are abnormal. Solution: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 68 BT antenna spring are reinstalled? Is the problem solved after the BT antenna is replaced? Is the cabling between the antenna and U4201 damaged or short-circuited? Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 69: Accelerometer

    U8860 Maintenance Manual 9 Principles and Troubleshooting 9.4.12 Accelerometer Circuit schematic diagram Signal Description I2C_SCL_HW I2C bus I2C_SDA_HW ACCE_INT Accelerometer interrupt signal ACCE_INT2 Accelerometer interrupt signal (sleep)—— Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 70 12-bit ADC, and is transmitted to the chip's DSP for data processing. The interrupt signal and data signal are outputted for data transmission with the main chip. Troubleshooting process: Failure: Relevant functions of the accelerometer are disabled. Solution: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 71: Compass

    Are the components on the accelerometer’s power supply circuit and control circuit damaged or short-circuited? 9.4.13 Compass Circuit schematic diagram Signal Description I2C_SCL_HW I2C bus Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 72 Is the problem solved after the sensor is replaced? Are the components on the sensor’s power supply circuit and control circuit damaged or short-circuited? Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 73: Gyroscope

    The gyroscope's core is a dipole. When the gyroscope is working, the core vibrates on the three axes' directions. If the phone rotates, because of the Coriolis force, the rotation will be Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 74: Touch Panel

    9.4.15 Touch Panel  Touch panel's circuit unit is a module fixed inside the touch panel. Its interface circuits are as follows: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 75 V power, and then supply the 1.8 V power; otherwise, the touch panel is disabled. When the touch panel is operating, the I2C controls data transmission. Four touching key fields are added to the U8860's 4-inch capacitive touch panel, and four backlight LEDs for the four keys are added to the touch panel module.
  • Page 76 Is the problem solved after the FPC is replaced. Are the components on the touch panel’s power supply circuit and control circuit damaged or short- circuited? Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 77: Approach Sensor

    The I2C bus controls the approach sensor components and data transmission. The interrupt pin provides the interrupt signal. The approach's internal structure is shown in the following figure. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 78 When the approach status achieves a certain threshold, the system triggers the operation to shut down the touch panel. Troubleshooting process Failure: The approach sensor is faulty. Solution: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 79 Is the problem solved after the FPC is replaced? Are the components on the touch panel’s power supply circuit and control circuit damaged or short- circuited? Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 80: Solder Points On The Pcb And Bga Chip

    10 Solder Points on the PCB and BGA Chip Solder Points on the PCB and BGA Chip Red (R:255,G:0,B:0) :Solder point Green (R:0,G:255,B:0) :Vacant point Main board diagram: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 81 U8860 Maintenance Manual 10 Solder Points on the PCB and BGA Chip Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 82 U8860 Maintenance Manual 10 Solder Points on the PCB and BGA Chip Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 83 U8860 Maintenance Manual 10 Solder Points on the PCB and BGA Chip Partial amplified figure: Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 84 U8860 Maintenance Manual 10 Solder Points on the PCB and BGA Chip Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 85: Functional Tests

    U8860 Maintenance Manual 11 Functional Tests Functional Tests 11.1 Keys Power key Volume Back to the Menu Back Search main screen Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 86: Mmi Test

    Check whether the environment light data is detected. When t light test approach you cover the approach sensor with hand, the number displayed sensor's on the LCD should be around 10. environment light sensing function. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 87 (Note: A terminal with WiFi function enabling is required to assist this test.) The MMI test is complete, and the test results are displayed on the LCD. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...
  • Page 88: Voice Call Test

    If no problems are found during the test, finish the voice call test. If any problems are found, troubleshoot the phone or send it to an advanced service site for repair. Issue 1.0 (2011-11-14) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd...

Table of Contents