[FUBAR] LB 820-2879 B no green or orange light (needs SMC)

[Mac-N-Sauce]

ok, i replaced the u7000(ugh that was hard) you make it look so easy. I am jealous. I now have 3.18v on pin 14 and up on pin 1 and 2 of u6901 but no 3.42v on pin 4. Is my pin 14 too low or my u6901 garbage?

 

[dukefawks]

I still say there is no 3V42 on pin 5 of U6901! If pin 5 is ok then U6901 is the next suspect.

 

[Mac-N-Sauce]

you are correct there is no 3.42v on pin 5, what am i missing here

 

[dukefawks]

So I have PP3V42_G3H on the one wire circuit coming through pin 1 of C6908 and other areas. How do I know if i have a bad U6901 vs a bad via?

3V on C6908 and nothing on pin5 of U6901. I hope you can figure out the rest.

 

[larossmann]

you fix the ONE WIRE circuit by running........ ?

Finish my sentence.

Here's a hint

https://www.youtube.com/watch?v=f1TKQwsWaOY

 

[Mac-N-Sauce]

No Title

ok, first i have attached some photos for you guys to have a good laugh! Louis you have nothing on me when it comes to bad soldering!
Second, I now have 3.36v on u6901 pin 5. i followed the path on the diagrams you sent, still no green light. i have 4v on pins 17,18 for u7000
I need the 12v ppbus_g3h

 

[larossmann]

Dude that is fucking scary. You need one strand of wire for this!!! Why do you think they call it the onewire circuit

You have 3.36v on pin 5, but what about pin 4? Is it outputting voltage now?

U6901 is a logic gate that, when SMC_BC_ACOK is present, will allow PP3V42_G3H to pass to output. The idea here is that it will power U6900 which allows the charger to talk to the SMC if the ISL6259/U7000 says that it is ok for it to. So follow to the next logical step - is U6900 getting 3.4v? Is U6901 shooting out 3.4v for U6900? If not, why?

 

[Crizz]

You use a coax-cable from a mic or webcam for the jumper... try to use a wire from a dead battery!

 

[Mac-N-Sauce]

I have 3.36 v on pin 4 and 5 of u6901 and pin 1 of u6900 and on pin 4and 5 of u6900 its 3.36v as well. I guess thats why i am confused. I jumped a wire to the u6901(although poorly done) to get my 3.4v to pin 5 and it appears to be getting to u6900

 

[Mac-N-Sauce]

No Title

Just wanted to show a better job of adding the wire. What is the product you use to insulate the wire? Green light on charger in picture 3! So we now have one wire, but no orange with battery connected.
So off I go to this one. I only have 4v on the charging circuit. Also can not power on with power pads

 

[larossmann]

circuitworks cw3300g is good for me. it looks like you have a green light, or is that just the flash?

 

[aprendiz]

12.6V on F7040? PP3V3_S5_REG on L7220?

 

[Mac-N-Sauce]

it is green light but i only have 4.57v on charging circuit f7040,

 

[Mac-N-Sauce]

if i understand correctly, something is pulling down the power to much form the 18.5v

 

[Crizz]

If your PPDCIN is 18.5V but PPBUS_G3H is only 4.57V there is maybe something pulling it down! YES
Probe with your fingers if something is getting hot.
Desolder F7040 and measure the voltage on pad1 of F7040
Are you able to inject 12V to PPBUS_G3H with an external power source?

 

[dukefawks]

I bet the 6259 is not soldered correctly or died in the process.

 

[Mac-N-Sauce]

i pulled the fuse and had same 4.57v on pin 1, changed the 6259, now i have 15.5v at the fuse, q7030 pin 5 is 16v and pin 4 is 18.4v
so i have gone from too low, to too high

 

[larossmann]

q7030/q7035 killed the isl which then killed the q7030/q7035. replace them all in one foul swoop and make sure your soldering is correct. This video sucks, but gets the point across. https://www.youtube.com/watch?v=JTS0rkx_JAQ

 

[Mac-N-Sauce]

Ok, I am having a hard time with the isl, lack of experience. The components are so close around it making it difficult to clean up pins. I just watched one of your videos where you had a large solder ball on the center pad of the isl. then you pressed it down to squeeze it out. I am using the curve tip. Should I switch to a straight point to clean it up after?

 

[Mac-N-Sauce]

I know I am getting close to the fix so I am excited. My daughter keeps making fun of me!?