Today we will share a repair service case of an apple iphone 12 that is unable to switch on Press the power switch and the phone won’t turn on Attach the phone to power and the phone still won’t switch on Disconnect the screen Power up the motherboard Please be noted that the time for powering up should not be too long It can be seen that the existing worth is large The motherboard has a large present which indicates the motherboard is short-circuited Next, we need to eliminate the motherboard and situate the damaged part for repair service Measure the diode worth of PP_BATT_VCC line with a multimeter The diode worth is 0 It can be validated that PP_BATT_VCC line is short-circuited PP_BATT_VCC line and PP_VDD_MAIN line of iPhone 12 are attached in collection by an inductor So the short-circuited PP_BATT_VCC line may also cause the PP_VDD_MAIN line to brief circuit The old solution to fix the large current issue is through rosin detecting With the melting of rosin, we can confirm the damaged part Though the solution is low-cost and efficient, it has some imperfections The motherboard has to be covered with rosin while the rosin is difficult to tidy up later On top of that, we need to get rid of protecting covers on the motherboard for an extensive assessment There is no question that procedure problem will be significantly improved Today we will present an advanced and reliable method to try to find brief circuit on the motherboard with the assistance of a Thermal Imager Cam The thermal imager finds the component of which temperature is greater than normal worth using infrared radiation The thermal imager can find motherboard electrical leak within seconds The malfunctioning components will certainly be found in no time at all once you place the motherboard under the cam, greatly boosting fixing performance While examining total motherboard working conditions, the thermal imager can pinpoint damaged components with high precision In addition, the thermal imager is an expert in detecting small electric leakage, short circuit and other issues with easy and safe operation, substantially lowering the error rate First off, we put the motherboard on the working platform Attach the black probe of the straight power supply to the ground and connect the red probe to PP_BATT_VCC line The temperature level on the top left corner has actually increased up The faulty component can be validated on the top left corner Open up the bitmap We can see that PP_BATT_VCC line is not on the top left corner Given that PP_BATT_VCC line and PP_VDD_MAIN line are linked in series by an inductor, we can evaluate that PP_VDD_MAIN line is short-circuited With inductors of PP_BATT_VCC line, click another side of the inductors The opposite side is connected to PP_VDD_MAIN line We can again identify the variety of faulty component It can be seen on the bitmap that the PP_VDD_MAIN line is on the reasoning board Following, we separate the motherboard Put the motherboard on the 170 ° C Heating System to warm Remove the motherboard After the reasoning board has actually cooled down, power up the reasoning board Connect the black probe to the ground and connect the red probe to PP_VDD_MAIN line With the thermal photo, we can now verify the defective part The capacitor is flawed with charring Get rid of the capacitor Tidy the bonding pad with PCB Cleanser Measure the diode values of PP_VDD_MAIN line and PP_BATT_VCC line The diode values return to regular The brief circuit fault has actually been gotten rid of Then we recombine the motherboard Assemble the phone to check The phone switches on normally Wi-fi and baseband work well IMEI number can be seen The mistake has been removed You can buy the Thermal Imager Video camera on REWA store Please do not hesitate to call our account supervisors or customer care group for even more information Thanks for watching
