820-2530 wont turn on

Kyle

New member
This came in with water damage, put it in the ultrasonic cleaner and have a green/orange light but wont turn on. U7840 was burned so replaced it but still wont power on. I have 12V but no 3v or 5V

I am new to component level repair. What should I check next?
 

larossmann

Administrator
Staff member
resistance to ground on PP3V42_G3H.

and for corrosion around the BIOS area. there is some ppvttcpu thing next to the bios that always corrodes on those.
 

Kyle

New member
No Title

Bios area looks real good with no corrosion. First picture is where U7840 was replaced. What else should I check? I have 3.3V around the U7200 area
 

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Kyle

New member
When I type that into the board view so many different components appear. Which one am I measuring?
 

JorgePayar

Member
Kyle you must put your multimeter in resistance mode, then you put one wire in ground and the other one in pp3v42_g3h line (it doesnt matter where) and measure the resistance to ground of that line, measure it and post the value. Like if it were a resistor.
 

larossmann

Administrator
Staff member
You are answering questions I didn't ask! I do not care what voltage is on PP3V42_G3H. What is the resistance to ground on that bus? You can measure anywhere on the board, at any point. PP3V42_G3H shows up everywhere.

Think of it like me asking for the temperature and weather in area code 10009.

I can measure the temperature outside my store

I can measure the temperature outside the school across the street.

I can measure the temperature at the grocery store next to the school.

It will be cloudy and raining, at around 47f in any of these locations. :)
 

bighead

New member
That's impossible you have green/orange light on the charger and you measured 0 Ohm on the PP3V42_G3H rail!
 

larossmann

Administrator
Staff member
Something is wrong here. Are you in resistance mode? Are you measuring resistance WITHOUT power connected? You can't have 0 ohms of resistance to ground on a line if you also have 3.42v present on that same line.
 

larossmann

Administrator
Staff member
2.6 what exactly? We need more information, try to be thorough with units of measurement. 2.6 ohms, kilohms, megaohms?
 

Kyle

New member
Also, I checked F7000 and am only getting 12.20VV, since its suppose to be 12.60V does this mean I have a bad smc?
 
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