1 press the power button when the current table without any reaction. This situation mostly appear in the starting circuit abnormal condition.

The main reasons are:

(1) the battery contact pieces damaged power cannot be sent to the power integrated circuit;

(2) the power button contact;

(3) the power button to power integrated circuit trigger circuit between the weld phenomenon of foot;

(4) the power integrated circuit damage;

2 press the power button, the current is not up to the maximum value. Source of failure in a radio frequency circuit or the transmit path. Because of large emission current amplifier, we can observe the current judge whether emission. General power of search network under normal circumstances, the current table should have a jump, but due to the different types of mobile phone current are not the same, so can not determine that the current reaches much value is normal, the general can reach more than 300mA.

3 press the power button, current meter indication, but does not swing, this is mainly software fault. With current indication, the hardware circuit has been working, but the current table does not swing, indicates that the control system can not work normally, the main software failure, should be processing software.

4 press the power button, ammeter pointer instantly reach full offset, power protection shutdown. This situation is mainly mobile phone internal short circuit or leakage caused by the filter capacitor. Normal circumstances should be the moment of starting current is about 200mA, the standby current is about 50~100mA, and the pointer swing without stop, emission current is about 300mA, the standby to launch a jump.

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