Macbook a1466

[String2016]

I have here macbook air a1466 820-3437-b the problem stuck for 1month and now the laptop not turning on. plugged in the charger goes to green light blinking and the stead at orange light nothing happen.I have checked PP3V42_G3H C3740 on the schematic it shows 6.3v but only measured 3.4v and PP3V42_G3H C4650 schematic shows it must be 10v but measured only 3.4v, the R4650 Resistor in schematic shows 100k but measured 94k. anyone can help me on this please

[mon2]

Re: Macbook a1466

3v42 is the correct voltage here.

The other values are the rated voltage for the capacitors.

What is the voltage of ppbus_g3h ?

[String2016]

Re: Macbook a1466

ppbus_g3h R5450 Both pins have 8v and chip U5450 Pin 4 and 5 IN have 8v both but pin 6 out no voltage.and ppbus_g3h R5501 in the schematic supposed to be 100k but measured only 20k fluctuating reading

[String2016]

Re: Macbook a1466

anyone could help please

[SMDFlea]

Re: Macbook a1466

anyone could help please

https://logi.wiki/index.php/PPBus_G3H

[String2016]

Re: Macbook a1466

U7100 CHIP connected c7115 in the schematic supposed to have 10v but it read one side 0.5v and other side 1.4v only and C7116 supposed to have 16v but only reading same voltage on C7115

[reformatt]

Re: Macbook a1466

Mate you are all over the place. Start over and begin with the basics. Board outside the case, no battery, plug in a LIO board and flex, apply power via Magsafe. These boards should power on automatically. You should have PP3V42_G3H @ 3.42V (which you must have since you have green/orange light), PPBUS_G3H @ 8.3V (or 8.6V if SMC is running) and PP3V3_S5 @ 3.3V. Then you troubleshoot S4 state from there.

PPBUS_G3H will measure lower if the battery is connected so you leave that out during troubleshooting. 820-3437 boards will also do a couple of stop/starts on fan spin before booting.

[String2016]

Re: Macbook a1466

board is outside the case tested plugged in magsafe turns orange then green then orange light nothing happens even battery unplugged

[mon2]

Re: Macbook a1466

Measure:

PPBUS_g3h
PP3V3_S5

After the above, do review this great website & webpage on topic on the required sequence of voltage rails and events before the logic board will power up:

https://www.it-tech.com.au/mac-q-a/pm-slp-s4-l-timing/