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Yes, the board is out of the case, just with DC IN, trackpad, Mini display port and HDD on USB.
Values in diode mode on a good board on SMBUS_BATT_SCL and SMBUS_BATT_SDA is 0.52V, so this seems ok
PP3V42_G3H_SMBUS_SMC_BSA=3.42V also ok
On the other hand, on the good board R5280 and R5281 = 2 kohm, and I have 0.9 kohm. So, this means issue on SMC or U7000?
What is the DC voltage showed by DC voltmeter on the SCL/SDA lines of battery bus: 0V, with or without battery connected
Check continuity from battery connector to R5280/81: traces are ok, continuity is 1 or 2 ohm
Do you get 3V at any pin of these resistors?: no, I get 0V, the same as at the battery connector.
The trace I showed in the previous post is all I get, either on R5280/81 or on the battery connector (so 0V, just square waves every second)
Can't we assume that the entrances of SCL/SDA lines on SMC or U7000 have an issue? The values of R5280/81 I measure are 0.9 kohm and not 2k, it could be an internal partial short with PP3V42_G3H ?
I checked for water damage around SMC or U7000, seems ok
"Do you get 3V at any pin of these resistors?"
Pay more atention to the questions in the future; you save time.
Very strange to get 0V on both SCL/SDA lines, with 0.480 in diode mode.
Check if R5280/81 are really good; 2K (ohm scale) out of board.
Please be sure your readings are correct.
I removed both R5280/81, indeed they are 2 kohm.
I removed U7000, then in diode mode I still have 0.54 and 0.55V on SCL/SDA lines. When I measure resistance where R5280/81 should be, I have 10 kohm
Replaced both R5280/81, voltage on pins 2 remains 0V, without U7000
So, only SMC remains to give these bad values?
Removed D6950: same story
Then I first simply heat SMC, and I finally got 3.4V on SCL/SDA lines.
Voltage went back to 0V on SDA line and around 1.5V on SCL line after total cooling down, so now assuming an SMC issue.
For the moment I don't have another SMC for this board, So I would like to use it without battery charging option.
So I put back D6950, U7000, but now the board does not start anymore (SMC_ONOFF_L to ground). I could start the board before heating the SMC, even without 3V on SDA/SCL lines. What is going on now?
PPBUS_G3H=0V
On U7000:
1 = 0V
2 = 17.4V
3 = 4.3V
9 = 0V
12 = 3.4V
14 = 3.4V
15 = 0V
17 = 0V
19 = 5.1V
20 = 5.1V
27 = 17.2V