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I have a 13 inch touchbar that is drawing 5v from the charger, I have a short to ground on ppdcin_g3h, I have removed all the cd3215s all the caps on that line and even all the transistors (Q3200 ect) short remains, its a 1 ohm short and I cannot find it for the life of me
You should remove R7020 first.
First suspects are Q7030, U7000, or one of the caps from PPDCIN_G3H_CHGR line.
Check resistance to ground at L7030 and F7000.
removed r7020, q7030 and u7000 also removed all caps on ppdcin_g3h_chgr still have 1 ohm to ground on ppdcin_g3h
1 ohm to ground on f7000
16k ohms to ground on pin 1 L7030 (tba_phase1)
456k ohms to ground on pin 2 of L7030 (tba_phase2)
"removed all caps on ppdcin_g3h_chgr"
Removed why, if the short is before R7020???
"16k ohms to ground on pin 1 L7030 (tba_phase1)
456k ohms to ground on pin 2 of L7030 (tba_phase2)"
Impossible!
Unless L7030 is open, which I doubt.
Check in diode mode, red probe to ground. Only switch to ohm mode, for very low value (i.e. less than 010).
Please, post accurate information, or our replies will not serve for anything...
"1 ohm to ground on f7000"
This is bigger problem, as it can be caused by shorted MOSFET in one CPU power spupply.
Check if any big coil has the same value.
Next check between PPBUS_G3H and that coil; ohm mode this time.
If you get less than 1 ohm, there is a shorted high-side MOSFET on that coil.
If get 2 ohms, check other coils.
On PPDCIN_G3H you can try to inject tension.
Start with 1V and go up, maintaining ampers bellow current limit of your bench power supply.
I was removing caps before i took off r7020 that was my bad
L7030 is around 500k ohms to ground on both sides im not sure why I got that messed up reading the first time
im getting about 1.5 ohms to ground on f7000, all big coils around the cpu are between 2-5 ohms to ground
I dont have a bench power supply so im unable to inject voltage
You can safely inject voltage on PPDCIN_G3H at this moment.
Always use the same method.
"Start with 1V and go up, maintaining ampers bellow current limit of your bench power supply."
No reason to go for PPBUS_G3H if you cannot solve PPDCIN_G3H problem first...
Looks like both power rails meet inside the board; very strange.
Did you check CB701 out of board?
Does the short disappear from any rail, after removed it?
yeah that cap is gone theres a litteral hole in the board under where the ppbus_g3h pad was, it goes all the way through to the other side, right on the other side of the board is another cap on that same line, i can see through the board now with both caps off. Both lines are still shorted to ground 1.7 ohms to ground
The last option you have, try to clean internal border of that hole.
Use a tiny drill and polish the interior.
Pray that no signal line pass in that area.
i tried drilling the hole, inside the bigger hole i can see where the layers are visibly black and there is cavity, in order to drill out the cavity the hole would impact surrounding components. this board is dead, thanks for the help with everything