G700-U10 Smartphone
Maintenance Manual
10 Circuit and Failure Analysis
Issue 1.0 (2013-07-22)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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10.3.4 GPS Channel
Circuit Diagram
Figure 10-25
GPS channel
Circuit Analysis
The GPS signals pass through the antenna and a group of the matching circuit and enter the
SAW filter. The signals are then amplified by a low noise amplifier and enter the MT6628Q.
Troubleshooting Process
If no GPS signals can be received by the phone, first check whether the antenna and antenna
springs are properly connected. If yes, check whether the LNA back end has signals (the GPS
module has no RF switch, use an RF cable for the inspection). If not, replace the LNA. If the
circuit has no missing component but the problem persists, return the phone to Huawei for
repair.
10.3.5 Wi-Fi Channel
Circuit Diagram
Figure 10-26
Wi-Fi channel
Circuit Analysis
The Wi-Fi signals pass through the antenna and a filter and enter the balun in the shielding
case. After this, the signals become differential signals and enter the MT6628Q.
