gateway ne56r/acer e1-531 cpu core voltage missing

[vickey_vip]

hello friends i have a acer gateway laptop
mb part no is q5wv1 la-7912p rev 2.0
my problem is when i power on laptop it on for 20 second and then off automatic and again it on automatic. when it on i am not getting any voltage on cpu core coil i am attaching schematic of this borad please help me i am not getting any voltage on pl20 pl21 and pl22

i replaced pu13 (ISL95836HRTZ) and processor But problem is still same also i flash bios but issue not resolved

i check pu13 voltage i am not getting +3vs supply on pin number 19 & 36
when i check connected register on those pins voltage is present on register other side. is this an issue ?

any help please
thanks in advance

[mcplslg123]

Re: gateway ne56r/acer e1-531 cpu core voltage missing

check R372/R368/R28. Are you getting VR_ON at pin 121 of kbc??

[vickey_vip]

Re: gateway ne56r/acer e1-531 cpu core voltage missing

both register R372 AND r368 OK AND GETTING 19v on register both side

i can't find R28 which is connected with u2 on schematic can you tell me where is in board

and VR_ON Available on kbc pin 121

[mcplslg123]

Re: gateway ne56r/acer e1-531 cpu core voltage missing

Check PU9. In many cases if it is defective you wont get cpu core voltage. Have you checked +vs signal?? Are you getting 3v/1.5v/5v vs voltages??

[abbassink]

Re: gateway ne56r/acer e1-531 cpu core voltage missing

Check PU9. In many cases if it is defective you wont get cpu core voltage. Have you checked +vs signal?? Are you getting 3v/1.5v/5v vs voltages??

Thanks brother my problem was resolved by changing pu9