(347) 552-2258 [email protected]

820-4924 no power

Jeffotskie26

Jeffotskie26

Member
hello i have a1502 when i recieved q7310 is over heating so i decided to replace it (no more overheating Q7310)
but still cant on i have orange light no fan spin. PPBUS_G3H 12.6V pin 1 2
and i just notice F4800 0.0V with 0.0000 diode to ground.

ALL_SYS_PWRGD is missing.
removed Q8150 ALL_SYS_PWRGD still missing.
 
2informaticos

2informaticos

Administrator
Staff member
"PPBUS_G3H 12.6V pin 1 2"
What this means?
Can you provide usefull information?
Pin 1 2 of who???

You've said short to ground at F4800.
Still the same disconnecting trackpad?

Why would you check ALL_SYS_PWRGD if machine can't on?
 
Jeffotskie26

Jeffotskie26

Member
im sorry what i mean f7140 pin 1 2 is 12.58v

f4800 is no voltage also no resistance to ground (not shorted)
theres no reaction on my tester with o without charger connected.

ALL_SYS_PWRGD this no idea i just check and notice this is missing too.
 
2informaticos

2informaticos

Administrator
Staff member
"i just notice F4800 0.0V with 0.0000 diode to ground
----------------
f4800 is no voltage also no resistance to ground (not shorted)"
???
Please post accurate information.
F4800 is not important here, but if mess other important things...

Do you get 3V3_S5/SUS?
 
2informaticos

2informaticos

Administrator
Staff member

HOW TO collection

I hope this "How to" collection will help our members. I will possibly modify this post in time, if updates available. Trigger SMC_ONOFF_L (PMU_ONOFF_L): It reffers to simulate power button function, when the keyboard is not connected. We need to do this when we work with the board...
boards.rossmanngroup.com boards.rossmanngroup.com
Didn't read it before?
 
Jeffotskie26

Jeffotskie26

Member
Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L.?


i tried put a wire to smc on off l then i touch to the ground of the board nothing happens
pwrbtn_l not sure how to check the pulse but i tried measure the voltage 3.4V stable
 
2informaticos

2informaticos

Administrator
Staff member
Do you have 3V at SMC_ONOFF_L?
It should drop to 0V when trigger it; just temporar contact to ground, like 1s.
You must check PM_PWRBTN_L reaction at the same time.

And PLEASE, write the signal names correctly!
 
2informaticos

2informaticos

Administrator
Staff member
Try to post ALWAYS accurate information.
If not, the help can be useless; as it is based on your replies!

If PM_PWRBTN_L reacts, then check for pulse at PM_SLP_S4_L (at the same time, of course).
 
Jeffotskie26

Jeffotskie26

Member
PM_SLP_S3_L and ALL_SYS_PWRGD have the same reaction? yes it is.
from 0.0V up to 3.2v when triggering SMC_ONOFF_L

smc bypass mode failed. (no reaction)

lets go back to my original post.

i mentioned that the q7310 is overheating.
now i tried removed again the q7310 chip and i test (diode to ground q7310 from board pin 1 2 3 CPUVR_PHASE1 is 0.0001
compare to working board it was 0.0053 what does it mean? is it cpu short circuit? is this the real problem?
is there something that i can still do to solve the issue?
 
Last edited:
2informaticos

2informaticos

Administrator
Staff member
I don't think Q7310 is bad; you've said to have short on board WITHOUT it soldered.
If was shorted, no way to get PPBUS_G3H also.

Q7311 can generate short to ground.
Remove L7310 and check where the short remains.
If will remain on R7310, very likely CPU is fried...
 
You must log in or register to reply here.
Top