His cell phone, electric, found to have serious leakage, leakage current is about 0.5 A, also quite serious. Can press the power button, mobile phone boot, current in o. about 6 ~ 0.7 A beating, the final stable between 0.5 ~ 0.6 A, A signal, but no emission. According to the above phenomenon, a preliminary judgment is as follows: 7mMservice manual download site
Plus electric leakage, its fault can be: power supply module is damaged, and battery anode are interlinked to ground when the components (such as: electrolytic capacitor, reverse protection diode, etc.), charging circuit, power amplifier could damage. 7mMservice manual download site
According to the mobile phone can normal boot and a signal, can be removed the possibility of power IC is damaged because of the power supply IC if damaged, so the power supply output is not normal, the power supply output is not normal, the radio frequency circuit does not work properly, so it should not have signal (signal means receiving circuit work properly). 7mMservice manual download site
The rest of the point of failure probability are exist, which most likely? Through inspection trace of mobile phone repair in several locations, and it is covered in rosin, or cleaning to say again first! 7mMservice manual download site
Mobile phone power up after cleaning, commissioning, the phenomenon has not changed. Is to estimate the artificial damage, so, in turn, check the power amplifier circuit, charging circuit, ground protection circuit, etc. When remove the power amplifier, the leakage found that cell phones don't ran, we can determine the basic power amplifier is damaged and lead to leakage. .7mMservice manual download site