User's Manual

Repair steps:
1. Check if the T card connector’s COM1 has quality problem, metal contact points abnormal;
2. Check if T card connector and components around have soldering problems;
3. If still failed to find out problems, check whether U1 chip has soldering or
performance problems.
b) Charging function abnormity
Repair steps:
1. Check if the USB J1 socket pins rust or have soldering problems;
2. Check if the battery connector’s metal contact well or not, such as existing foreign
matters, rusting or soldering badly, etc;
3. Check if the relevant components of the charging circuits have soldering problems;
4. Replace with new battery, and verify again;
5. If still failed to find out problems, check whether U1 chip has soldering or
performance problem.