Step By step Repair 1st boot error

when we have dead phone and when we flash that phone then we found error message "1st boot Error"....

thanks mean the CPU of the phone is not work...


but we cant judge that CPU damaged....!!!

why???

because for normally working... CPU need some Working Condition...




CPU Working COndition for DCT4


Vio = 1.8v (come from UEM to CPU)
Vana = 2.8v (come from UEM to UEM)
Vcore = 1.4v (come from UEM to CPU)
Vr3 = 2.8 v (come from UEM to RF Ic or Oscilator 26Mhz)
Purx = 1.8v (come from UEM to CPU)
Sleepx = 1.8v (come from CPU to UEM)
Sleep Clock = 32.768khz (Come from oscilator 32.768 to UEM to CPU)
Rf Clock = 26Mhz (Come from oscilator 26Mhz to RF Ic to CPU)





CPU Working COndition for WD2


Vio = 1.8v (come from UEM to CPU)
Vana = 2.8v (come from UEM to UEM)
Vcore = 1.4v for CPU v 3.2 and 1.8v for CPU v2.5 (Come from SMPS Ic to CPU)
Vr3 = 2.8 v (come from UEM to RF IC/oscilator 26mhz)
Purx = 1.8v (come from UEM to CPU)
Sleepx = 1.8v (come from CPU to UEM)
Sleep Clock = 32.768khz (Come from oscilator 32.768 to UEM to CPU)
Rf Clock = 26Mh (Come from oscilator 26Mhz to RF Ic to CPU)




CPU Working COndition for BB5

Vio = 1.8v (come from Retu to CPU)
Vana = 2.5v (come from Retu to Retu)
Vcore = 1.4v (come from Retu to CPU)
Vr1 = 2.5v (come from UEM to RF IC/oscilator 38.4mhz)
Purx = 1.8v (come from Retu to CPU)
Sleepx = 1.8v (come from CPU to UEM)
Sleep Clock = 32.768khz (Come from oscilator 32.768 to UEM to CPU)
Rf Clock = 38.4 Mhz (Come from oscilator 38.4Mhz to RF Ic to CPU)




Vio = Voltage Input Output
Vana = Voltage Analog
PURX = Power Up Reset X





If.....

No voltage for Vana.. u can make jumper from Vr3
no voltage from vr3.. u can make jumper from Vana



please share about dead phone problem....

but with measurement result ok.....