Hardware Advice's for Technicians Read Before Rework!
Most important in repair when you receive an device for repair is first INVESTIGATION under stereo-microscope entire board to OBSERVE damaged,missing,corroded,burned etc components. Communicate to the costumer to find out what is the main cause came from.That is the best method to detect the fault first.
Knowledge about parts and those function is necessarily need.I saw a many mobile technician who have no idea about parts and engaged on repairing.so,function about the parts is highly RECOMMENDED.
Always use dc power supply,to observe shorting or leakage or use multi meter.
Not all filters or resistors can jumped with wire that is mistake,for example filter that stay near LCD connector for light if you jump it this will overload the IC and coil even PMIC and can burn as a result you will need to replace light coil or ic in place of small filter,this why to jump is NOT RECOMMENDED.Among them low value resistor you can jumped at all.
Never heat glued ic’s or chip as this is NOT RECOMMENDED,only re-balling will fix 100% loosen solder balls after device was dropped,fall,kick etc.
After changing any chips don`t forget to test shorting before insert battery.Because battery amp is too high,if short may be another parts makes damage.
If you want 100% help on this site you can post comment about faulty phone,water damaged,dropped,fall,kick,connected to copy China charger etc.
All readings that i ask here are done with multi-meter switched at diode/beep testing or if not available 2 in 1 function then use only diode testing,to make a reading hold Black probe to GND Red to Positive track and vice versa Red to GND and Black to Positive,so the track you take readings must have 2 different readings that you compare with working board and can see if there is no short.
It is recommended before do hardware repair on board,to test faulty board with known good working housing and LCD/Touch.
Feel free to ask anything here about rework!
Always do best as much as you can.
Most important in repair when you receive an device for repair is first INVESTIGATION under stereo-microscope entire board to OBSERVE damaged,missing,corroded,burned etc components. Communicate to the costumer to find out what is the main cause came from.That is the best method to detect the fault first.
Knowledge about parts and those function is necessarily need.I saw a many mobile technician who have no idea about parts and engaged on repairing.so,function about the parts is highly RECOMMENDED.
Always use dc power supply,to observe shorting or leakage or use multi meter.
Not all filters or resistors can jumped with wire that is mistake,for example filter that stay near LCD connector for light if you jump it this will overload the IC and coil even PMIC and can burn as a result you will need to replace light coil or ic in place of small filter,this why to jump is NOT RECOMMENDED.Among them low value resistor you can jumped at all.
Never heat glued ic’s or chip as this is NOT RECOMMENDED,only re-balling will fix 100% loosen solder balls after device was dropped,fall,kick etc.
After changing any chips don`t forget to test shorting before insert battery.Because battery amp is too high,if short may be another parts makes damage.
If you want 100% help on this site you can post comment about faulty phone,water damaged,dropped,fall,kick,connected to copy China charger etc.
All readings that i ask here are done with multi-meter switched at diode/beep testing or if not available 2 in 1 function then use only diode testing,to make a reading hold Black probe to GND Red to Positive track and vice versa Red to GND and Black to Positive,so the track you take readings must have 2 different readings that you compare with working board and can see if there is no short.
It is recommended before do hardware repair on board,to test faulty board with known good working housing and LCD/Touch.
Feel free to ask anything here about rework!
Always do best as much as you can.
Tags:
Guide for mobile repair.