Basically dead mobiles are called as not getting to turning on or not able to boot a mobile phone.

STEP 1:

Check battery.

• Most of the dead mobile phone problems are causes with battery and its performance.Approximately battery voltage is3.7v you can check this with using multimeter in voltage mode, if it is around 3.6v you can proceed to next step or else proceed in further.
• You can boost your battery with battery booster.
• After boosting your battery check the voltage again, if it is boosted at rated voltage you can proceed to next step. Or else change the battery and proceed to next step.

Note 1: if you have service station or DC machine you can check with that also.

Note 2: you carefully watch the battery performance after boosting.Because some cases battery will drain automatically after certain time. If you are facing this issue change the battery and proceed to next step.

STEP2:

Check board short or not.

You can check this on battery connector (+ve,-ve) terminal, in multimeter continuity mode.

• • If you get one side value 230 to 360 and other side open circuit (multimeter shows “1”) the board have not any complaint. so you can go to next step
  • If you get 2 side value, your motherboard is in half short so we have to remove that.
  • If you get beep sound while putting (+ve,-ve) terminal of battery connector, your  motherboard  is in full short condition you must remove the short, then automatically board will be work .hope you already learned  short removing in Mathi academy. If you have any doubt regarding that please contact immediately.

  STEP 3:

  Check power switch.

  You have to check cold and hottest methods. In cold test use multimeter in buzzer mode. During hot test you put multimeter on voltage mode.

  Cold test: test switch working or not in buzzer mode.

  Hot test: put the battery into battery terminal and check the voltage in power switch (above1.8v, it may vary up to 3.5V. depends on model)

  STEP 4:

  Check display section.

  • Check display strip is physically damaged or not
  • Check voltage on display connector ( you can get voltage on 2 or 3 pin of connector)
  • It comes then change the display.if not, probably you do IPA cleaning, heating and IC checking, jumpering etc…