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That is what I was thinking, thanks for confirming my suspicion.
Do you think it would be worth trying to heat up the CPU with some flux? What temperature and time frame would be good to try from your point of view?
Thanks again for your help!
Hello, I followed this post as close as possible because it sounded a lot like I have on this one
Below are my results so far, help!!
820-00840-a short on ppbus_g3h
R5400 pin 2 short
U7420 removed short gone have...
Update for reference.
Installed another U7800 chip short now gone. Still only 5v at the charge port. LED light stays on solid now also. Darn, thought that was it, but no.
My methods of checking voltages in order they are on the diagrams is bad for me. I should have checked core voltages and...
By removing the U7800 chip, short goes away. Installed another chip from a donor board same thing. Anyone run across this before? This is the only chip that immediately gets hot under infrared camera, rest of the board does not heat up when I force voltage on the PP3V3_G3H.
When you say secondary power rails, what rails are those? I checked all the rails on page 121. Is there another page that has the rails you are referring to?
As far as the U7800, do you know if there is firmware on that chip? Does your store sell those chips?
Thanks. I went ahead and replaced both CD3215 because there was a little corrosion around both. I now have 20v at usb meter but 0amps.
F7000 shows 12.63v but it cycles down to 0v and then back to 12.63v. it does this continually. I rechecked F7000 in diode mode and now I get OL reading and not...
So I take it from the direction this is going PPDCIN_G3H would be the first voltage to make sure is there before the others? Like the PPBUS_G3H was on older boards?
Does anybody know in what order should I check power rails as far as importance. Example, I do not have PPBUS_G3H. Should I just stop there and chase that one down first on this board, or is there another rail I must chase down first then chase down PPBUS_G3H.
On older boards, if I...
I do have a short on only 1 of the rails:
PP0V9_S0SW_SSD_CORE .001 diode mode .2 ohms
Verified with a working board same measurement on that line was .224 diode 365 ohms
There are alot of caps on that line? Also of course the ssd chip itself.