Mobile phone without a charger, but both on/off charging indicator. ERKservice manual download site
 ERKservice manual download site
1, tail plug leakage. ERKservice manual download site
Normally end insert, 17, 18 feet DCVOLT shows high level, can fly line insert tail sub 18 feet over the ground, and then plug in the battery, if the phone is no longer a false charge, shows that the leakage position in DCVOLT related lines, tail plug, U107 section (see figure 1, figure 3). ERKservice manual download site
 ERKservice manual download site
2, U105 leakage or breakdown. ERKservice manual download site
 ERKservice manual download site
 ERKservice manual download site
U105 open circuit fault, there will not be a false charge but if leakage, not even the first (2) feet. High level, on the first (3), (4) feet will conduction (because the leakage), make RTC3V3 voltage U105 first (3), (4) feet to DCIN side, for the high level to make the end, CPU charging instructions, display a charging symbol (see figure 2). The judgment method is: will U105 first (2) feet of fly line, and then plug in the battery, if no charging symbol, can judge U105 normal, failure positions in the first 2 feet U105 to end inserted between the first @ feet. If still appear after the fly line charging symbol, then remove U105, charging symbol disappear, explain U105 damaged, need to change. ERKservice manual download site
 ERKservice manual download site
3, D101 leakage. ERKservice manual download site
Isolation diodes D101 powered up for the first (1), (2) feet leakage can also lead to a false charge, may be from samsung other model mobile phone to take the same below model for detecting diode substitution (see figure 2). ERKservice manual download site
 ERKservice manual download site
4, circuit leakage. ERKservice manual download site
Judging circuit board leakage is more difficult, as we all know DCIN signals for the CPU charging testing point, if the point is high level, the CPU will issue a charging instructions. If you remove the U105 still charging indicator, the leakage could be DCIN lines. ERKservice manual download site
 ERKservice manual download site
For PCB leakage cleaning, drying and other treatments are available, and if the invalid, can plug tail 18 feet ground, if the charging symbol will disappear, but could not find the leakage components (parts), the point at which a to meet at this time can be a resistor to lower the leakage caused by the high level (resistance value can be decided by test, generally choose 2 k Ω Ω ~ 10 k), then U105 first (4) feet grounded, eradicate the charging symbol; If replace U105 is invalid, the same can be added in the first 4 feet U105 to resistance, the above method (see figure 2).

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