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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"...
Charger 5 V, 550 mA Flash memory ROM: 4 GB RAM: 512 MB Camera Y300-0000: 5 MP full-frame rear camera Y300-0100 and Y300-0151: 5 MP autofocus rear camera and 0.3 MP full-frame front camera Bluetooth WCN2243 Bluetooth v2.1 Wi-Fi 802.11b/g/n...
2.1 Applicable Scope This document provides repair instructions for technicians at service centers authorized by Huawei. Being Huawei proprietary, this document is accessible only for authorized service centers and companies. Although every effort was made to ensure the accuracy of this document, errors may still exist.
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Quantity BB shielding cover RF shielding cover Front camera (for the Y300-0100 and Y300-0151 only) PM shielding cover The components listed in Table 3-1 are structural parts of the phone, and cannot be used as reference when requesting spare parts.
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4 Components on the Main PCB The following component list is for your reference only and subject to changes without notices. The latest component list is available in Huawei's ITEM information system. If you have any question, contact your local technical support center.
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Step 2 After the installation is completed, click Close, as shown in Figure 5-4. Figure 5-4 Closing the dialog box Step 3 Power on the Y300, connect it to the computer using a USB cable, and click Device Manager to display the Computer Management window. Then, check that the port information is correct, as shown in Figure 5-5.
5.3.2 Performing a Normal Upgrade To perform a normal upgrade: Step 1 Power on the Y300, and use a USB cable to connect the Y300 to the computer on which the USB driver and 10KNewMu have been installed. Step 2 Double-click 10KNewMu.
Step 3 Insert the microSD card into the Y300 and power on. After the home screen is displayed, choose Settings > All > About phone > System update > Update via SD card > Confirm >...
Step 2 Create a folder dload in the root directory of the microSD card and copy UPDATA.APP from the main upgrade package to the dload folder. Step 3 With the Y300 powered off, press and hold the power key and the volume up and volume down keys to drive the Y300 to enter forcible upgrade mode.
Y300 Maintenance Manual 7 Disassembly Procedure Disassembly Procedure 2. Start to disassemble the Y300. 1. Wear the ESD wrist strap and ensure that the ESD wrist strap is properly grounded. 3. Remove the battery cover: Pry open the battery 4. Remove the battery.
Assembly Procedure 1. Wear the ESD wrist strap and ensure that the ESD 2. Start to assemble the Y300. wrist strap is properly grounded. 3. Assemble components on the front cover, including (1) receiver, (2) power key FPC, and (3) touch panel.
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8 Assembly Procedure 4. Assemble components on the rear cover, including (1) speaker, (2) GPS antenna, (3) Wi-Fi antenna, and (4) antenna support (and diversity antenna for the Y300-0100 and Y300-0151). 4. Assemble the LCD onto the front cover. 5. Assemble the standby PCB and accessories.
The Y300 is a UMTS bar-type phone developed by Huawei. It adopts the MSM8225+PM8029 chip solution provided by Qualcomm. The Y300's main PCB consists of the MSM8225, PM8029, and RF components. The main PCB connects to components in several ways, including: ...
9 Principles and Failure Analysis An integrated Y300 is consisted of the main PCB, structural components, and a battery. The Y300 supports multiple functions, such as the voice service, short message service (SMS), and microSD card storage, and can save contacts and text messages in the USIM/SIM card or the phone.
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Figure 9-3 Circuit diagram for startup management (2) Analysis The Y300 adopts the independent power management chip PM8029. The PM8029's startup process is controlled by Qualcomm's codes. When the PM8029 detects that the KPD_PWR_ON level is low, the PM8029 enables the startup process. During the startup...
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Startup faults can be divided into the following types: No current: After you connect the Y300 to the DC power supply and press the power key, the DC current ranges from 0 mA to 5 mA. ...
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DC current exceeds 300 mA. If the Y300 fails to be powered on, observe the DC current upon startup to identify the fault. Figure 9-5, Figure 9-6, and Figure 9-7 show the fault identification processes upon no current, weak current, and strong current.
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Figure 9-6 Fault identification process upon weak current The Y300 fails to be powered on. Install a simulated battery on the Y300, connect the Y300 to the maintenance power, press the power key, and observe the current. The current is weak.
Figure 9-7 Fault identification process upon strong current The Y300 fails to be powered on. Install a simulated battery on the Y300, connect the Y300 to the maintenance power, press the power key, and observe the current. The current is strong.
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A charger is connected to the Y300 but the Y300 does not respond. The Y300 displays the charging icon on the screen but in fact the battery fails to be charged. Handling: Check whether the I/O battery connector is damaged. Troubleshoot the fault according to the process shown in Figure 9-11.
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Y300 Maintenance Manual 9 Principles and Failure Analysis Figure 9-11 Troubleshooting process when the Y300 fails to be charged The Y300 fails to be charged after connecting to a charger. Replace the Does the charger charger. operate properly? Is the J901 dry Re-weld the J901.
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The 32.768 kHz oscillator delivers signals to the PM8029, which provides signals to the system. Troubleshooting Fault symptom: The Y300 fails to be powered on or frequently breaks down. Checks on the 32.768 kHz oscillator show that the X301 and U3101 have no output or the frequencies are unstable.
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The Y300 incorporates the 4 GB eMMC that uses the eight-bit data cable for transmission. Troubleshooting Fault symptom: The Y300 fails to be powered on, or the startup current is less than 100 mA. Handling: Upgrade or upload the system software, and verify that the VREG_DCDC_2P85 voltage and peripheral components are normal.
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Troubleshooting No reception Fault symptom: The Y300 fails to receive signals in the WCDMA 2100/1900/900/850 MHz and the GSM 900/1800 MHz receive channels. Handling: The WCDMA 2100 MHz frequency band is used as an example. Troubleshoot the fault according to the process shown in Figure 9-28.
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Y300 Maintenance Manual 9 Principles and Failure Analysis Figure 9-28 Troubleshooting process when the Y300 fails to receive signals The WCDMA 2100 MHz receive channel is faulty. Check U3201 before the RF cable is connected. Are pin 1 and pin 2 of U3201 properly Check the U3201.
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No transmission Fault symptom: The Y300 fails to transmit signals in the WCDMA 2100/1900/900/850 MHz and the GSM 900/1800 MHz transmit channels. Handling: The WCDMA 2100 MHz frequency band is used as an example. Ensure that the SIM card and antenna are properly installed and then troubleshoot the fault according to the process shown in Figure 9-29.
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Y300 Maintenance Manual 9 Principles and Failure Analysis Figure 9-29 Troubleshooting process when the Y300 fails to transmit signals The WCDMA 2100 MHz transmit channel is faulty. Check U3201 before the RF cable is connected. Are pin 1 and pin 2 of U3201 properly Check the U3201.
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Figure 9-32 LCD circuit diagram (3) Analysis The Y300 incorporates a 4.0-inch TFT LCD with a resolution of 800 x 480 pixels. The Y300's LCD uses the Mobile Industry Processor Interface (MIPI), requiring only two pairs of differential signaling cables and one pair of power cables. The LCD interface...
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Y300 Maintenance Manual 9 Principles and Failure Analysis Troubleshooting Fault symptom: The Y300 can be powered on, but the LCD displays nothing. Handling: Check the LCD. Troubleshoot the fault according to the process shown in Figure 9-33. Figure 9-33 Troubleshooting process when the LCD displays nothing The LCD displays nothing.
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Y300 Maintenance Manual 9 Principles and Failure Analysis Figure 9-39 Receiver circuit diagram (1) Figure 9-40 Receiver circuit diagram (2) The Y300 provides three kinds of audio output: Receiver output: Signals are delivered by the CPU. Speaker output: Signals are delivered by the PM8029 to the PA and then the speaker.
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After a call is established, no voice is received. Are components of left and right receiver channels dry jointed or deflected? Return the Y300 to Huawei for repair. Adjust the headset Is the receiver volume to a proper volume properly set? value.
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Fault symptom: The Y300 fails to transmit voices. Handling: Troubleshoot the fault according to the process shown in Figure 9-43. Figure 9-43 Troubleshooting process when the Y300 fails to transmit voices After a call is established, no voice is transmitted.
Figure 9-44 shows the headset circuit diagram. Figure 9-44 Headset circuit diagram Analysis The headset is tested using the GPIO_026's HS_DETECT_N after being inserted to the Y300: Before the headset is inserted, HS_DETECT_N is converted to high level by VREG_S3.
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Is voice heard after the headset is replaced? Is the HS_DETECT voltage changed Replace the after the headset is headset connector. inserted? Return the Y300 to Huawei for repair. Circuit Symbols Signal Symbol Description Reference Measurement or Waveform FM_ANT FM antenna...
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The PM8029 provides input and output signals to control the SIM card port. Troubleshooting Fault symptom: The Y300 fails to detect the USIM/SIM card. Handling: Check that the USIM/SIM card slot is normal. Troubleshoot the fault according to the process shown in Figure 9-48.
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Y300 Maintenance Manual 9 Principles and Failure Analysis Figure 9-48 Troubleshooting process when the Y300 fails to detect the USIM/SIM card The Y300 fails to detect the UIM card. Can the Y300 detect the UIM card after the UIM card is replaced?
When a charger is connected to the I/O interface, the charger provides the VCHG charging voltage to charge the battery. When a data cable is connected to the I/O interface, USB_HS_DN and USB_HS_DP are used for communication between the Y300 and computer (to upgrade the Y300's software and read its data).
Analysis The U1402 is used to provide the ESD protection and EMI filtering. Troubleshooting Fault symptom: The Y300 fails to detect the microSD card. Handling: Troubleshoot the fault according to the process shown in Figure 9-52. Figure 9-52 The Y300 fails to detect the microSD card.
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Figure 9-53 Circuit diagram of the FM and Bluetooth Analysis The Y300 integrates Bluetooth and the FM to provide functions, which are implemented by Qualcomm's WCN2243. Bluetooth uses an independent antenna and the FM uses the left- and right-audio channels as the antennas.
MMI tests include: Board test: The Y300 directly proceeds to the next test if the board test is successful. microSD card test: The message "No SD card available" is displayed if the microSD card is not inserted.
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Y300 Maintenance Manual 11 Functional Tests Step 2 Press and hold the power key to power on the Y300. Step 3 Check that the signal strength changes properly on a normal network. Step 4 Place a call to a fixed-line phone and check the voice quality during the call.
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