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820-2530 dim green light

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BCConnection

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820-2530

Some slight liquid damage signs around rear edge.

Thought ok probably damaged 3v42 line. Check it getting 3.38V seems low. No obvious damage around the boost IC.

Checked ACOK line from u7000 0v
Check ACIN 0v
Replaced u7000 due to internal short pulling ACIN low.

Now have 4v on ACIN and ACOK reads 3.3v

Still dim green light. Also inrush MOSFET first gate isn't opening, so no pp_g3h being made either.

Is this still a u7000 issue or is the 3v42 too low causing a weird issue.
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DCIN is 16.6 -16.8v and fluctuates quite a bit not a steady voltage
 
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18v5 input from DCIN keeps going from 16.1 to 16.6V it will slowly rise and fall.

I pulled u7000, D6905, and U6990 to see if would settle and its still bouncing. Tried 3 different DCIN boards and 3 different chargers. DCIN Rail reads OL in resistance and diode mode
 
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Yes ISL6258. I double checked after I pulled the first one. Ill get you a reading on ACOK line. Doesnt make sense to me that voltage on DCIN isnt holding constant. I asked Louis on live stream and he said it should be a steady voltage

Having removed U7000, D6905, and U6990 I was hoping to see this voltage stabilize but its still moving almost a full volt. Ill try a 3rd charging brick Monday to confirm that fully. Although the one I use on my other 13inch 2011 60W works just fine.
 
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Replaced SMC getting solid green light now but AGate pin 1 isnt opening the inrush mosfet. I have 16.4-16.9 on source and same voltage on the gate. No output to Drain.
 
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Still Dim green light but ACOK and 3v42 present

What doesnt make sense is ACOK is showing up 3.3v but there is no power on the Inrush pins from charger.
The AGate is at 16.7v (DCIN voltage) but the Mosfet is closed. Is this a voltage divider that must go to ground on AGate to make the first Mosfet open? I replaced the mosfet to rule out that and no change.
There are no shorts on the inrush line to u7000. ACOK reads in the MegaOhms and Ive replaced U7000 with a 6258 chip 4 times.
DCIN voltage isnt consistent it fluctuates from 16.2-16.9v. 3 different chargers all the same. 3 different DCIN boards all the same.
 
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Well Im back to this one. Replaced SMC and getting green light now but still dont have a switch from U7000 to open the inrush mosfet to start making PPBUS_G3H.

This is supposed to switch to ground correct so the voltage divider drops gate voltage low and opens?
 
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I confirmed that yes AGATE goes to ground to allow voltage in.

I pulled the chip and ACOK is still there I guess because this is a data line. So charger light is green.

Correct me if Im wrong but you get power on the computer.

3v3 and 3.42 lines come up with the charger.
3v3 feeds the ACOK line
3v42 and ACOK 3v3 tell SMC when the charger is preset along with the ACIN pin allows U7000 internally to work This should cause SMC to tell ISL6258 to ground the AGATE line and inrush mosfet opens.

Im not sure what part is broken here Ive put 3 SMCs on it and the data lines from SMC to U7000 are 3v or higher.
I cant imagine Ive installed every one of these ISL6258s wrong (Orientation is correct) and I cant imagine I have 3 bad SMCs.
 
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Well I feel dumb. The Diode that feeds Charger DCIN pin 2 of U7000 died and wasnt allowed 16v through.

I get boot on SMC bypass so I should be able to swap it and be ready to go.

Now I know what to look for
 
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