macbook a1706 820-00239

[PITERPENY]

the power button does not work on/off! the finger scanner works! tell me what to check?

[mon2]

Power button is often the edge contact of the FPC cable so do check for this.

Use tweezers on the PCB pcb pads for the power button bypass to confirm the logic board can turn ON/OFF

[PITERPENY]

I beg your pardon, but which contacts need to be short-circuited?

[PITERPENY]

the problem is definitely on the board side, since I connected other buttons of this model and they also do not work!

[mon2]

My bad. This model has the kooky touch button which is keyed to the logic board. If testing with other touch buttons then the fingerprint scanner will be lost. The on/off button action should still work.

Review the logic board side connector for this button assembly. Remove all power and test each logic board side connector pin in diode mode.

[PITERPENY]

J4900
1: PP1V8_MESA_CONN=0.493
2:MESA_SPI_MISO_CONN=0.457
3:GND
4:MESA_SNSR_INT_CONN=0.737
5:MESA_SPI_MOSI_CONN=0.457
6:MESA_BOOST_EN_CONN=0.740
7:MENU_KEY_L=0
8:MESA_I2C_SDA=0.448
9:MESA_SPI_CLK_CONN=0.483
10:MESA_I2C_SCL=0.449
11:PP16V0_MESA_CONN=0.624
12:GND
13-14:PP3V0_MESA_CONN=0.522
15-16:GND

[PITERPENY]

as I understand it, when you press the power button in U3900, a MESA_PWR_EN signal is generated, which activates the PP1V8_MESA signal on U4920, PP1V8_MESA activates the PP3V0_MESA signal on U4910, PP3V0_MESA activates PP16V0_MESA on U4900, which starts the MacBook! Or am I completely confused and all this is wrong?