820 4924 dead

EJS

New member
820 4924 no power, 12.59v ppbus, 3.42v pp3v42, 5v and 3.3v on s5 lines. Missing S4. Machine was water damaged sometime in the passed. Apparently the board was cleaned by another shop, and it worked for a while, now its dead.
 

2informaticos

Administrator
Staff member
Oeiginal 85W charger?
Post SMC_ADAPTER_EN, PM_BATLOW_L, PM_SLP_SUS_L, 3V3_SUS.
Also check all RTC signals.
 

EJS

New member
SMC_ADAPTER_EN 3.384v
PM_BATLOW_L 3.318v
PM_SLP_SUS_L 3.319v
3V3_SUS 3.321v

Unfortunately I do not have a scope to check RTC signals
 

2informaticos

Administrator
Staff member
There is only one oscillation to control with o-scope; 32KHz from pin 12/U1900.
You can post DC voltage at least; 0.45V is a good aproximation.
The other 4 signals are on page 12 and no need o-scope at all...
 

EJS

New member
PCH_CLK32K_RTCX1 .406v
RTC_RESET_L 3.320v
PPVRTC_G3H 3.321v
PCH_SRTCST_L 3.31v

Are these the ones I am looking for, did I miss any? Also while I was taking these voltages the fan randomly kicked on and now I have my s4 lines back...
 

2informaticos

Administrator
Staff member
You can try to heat/reflow CPU and SMC with good flux.
May be just crap remained under chips.
Can also be BIOS issue.
Do you get high level at pin 7/U1950?
Check all SPI termination resistors, page 47.
 
Top