FLY E185
Service Manual
CKT Confidential
Page 35 of 47
4.2 Display problem
LCD is connected by Solder FPC on the PCB directly. A bad soldering can lead to display failure,
so you can check it with your eyes firstly and then measure the Vcc Pin of LCD with digital
multi-meter. If the soldering is OK, maybe it is the problem of LCM or Main-board. You can
replace the LCM or check the display circuit on the main-board. What’s more, the phone’s
software, LCD setting also can make the display abnormal. So you can re-download the software
and adjust the setting. Otherwise, you need to replace the Baseband IC.
4.3 Charging problem
For charging issue, we need to check the below components to fix it. The components including:
Battery, Charger, Battery CON, Charger CON, 5PIN Micro USB System Interface, PMIC,
Charging circuit and Baseband IC. The software problem also can make the charging fail. So
when you face the charging abnormal issue, you can check these components one by one to find
out the problem and solve it.
4.4 Voice can not be sent or received
This issue often occurs in a mobile phone. You can enter into engineering mode by inputting
*#166*#, and then go to the test item “Receiver”. After press “On” button, you can hear a beep
sound if the receiver is good. Otherwise you need to test its resistance with digital multimeter. The
resistance of Receiver should be 32ohm. If the resistance is much bigger than the normal, it means
the receiver is defective, so you can change it for a good one. Secondly, in the test list item, select
another test item “echo” and test the MIC. Huff at MIC then there will be an echo at receiver that
shows the microphone is ok. Otherwise you must check the microphone bias circuit, test bias
voltage and output signal, microphone resistance should be 2.2k ohm.
