Macbook Air 820-00165

[Instafixx]

Hello,
We have a Macbook Air 820-00165 with No Power On and No Green/Orange Light in the charger.

PPBUS_G3H is at 8.19 Volts.
PP3v42_G3h also present.
Checked SMC and the JTAG connector too. Everything is fine. The board has no corrosion or anything.

Can you guide me as to what can be the solution for this?

[mon2]

Re: Macbook Air 820-00165

You need a solid voltage on PP3v42_G3h at 3v42 to see the green / orange lights.

If this voltage is ok on the main board then you may have contact issues on the magsafe connector.

Remove all power and confirm seating of the LIO cable and daughter board that has the magsafe connector.

With IPA and a cotton swab, clean the contacts on the magsafe connector. Test again.

Be sure the power adapter is an original.

[Instafixx]

Re: Macbook Air 820-00165

You need a solid voltage on PP3v42_G3h at 3v42 to see the green / orange lights.

If this voltage is ok on the main board then you may have contact issues on the magsafe connector.

Remove all power and confirm seating of the LIO cable and daughter board that has the magsafe connector.

With IPA and a cotton swab, clean the contacts on the magsafe connector. Test again.

Be sure the power adapter is an original.

We tried with a different charging board. No result.

[mon2]

Re: Macbook Air 820-00165

Measure and post the voltage checks of the attached points.

[reformatt]

Re: Macbook Air 820-00165

Hello,
PPBUS_G3H is at 8.19 Volts.

SMC isn't running. Check around U5110 and check SMC_RESET_L and PP3V3_S5_AVREF_SMC. If the former is low, then SMC is stuck in reset. If the latter is absent (shorted cap etc), then board will only run in SMC bypass.

[Instafixx]

Re: Macbook Air 820-00165

SMC isn't running. Check around U5110 and check SMC_RESET_L and PP3V3_S5_AVREF_SMC. If the former is low, then SMC is stuck in reset. If the latter is absent (shorted cap etc), then board will only run in SMC bypass.

SMC_RESET_L is 3.38V
PP3V3_S5_AVREF_SMC is 3.3V

[Instafixx]

Re: Macbook Air 820-00165

Measure and post the voltage checks of the attached points.

Hi, i have a noob question but i am unable to read this schematic. Can you please tell me the components?

[mon2]

Re: Macbook Air 820-00165

Measure at L7095.

[Instafixx]

Re: Macbook Air 820-00165

Measure at L7095.

Its 3.42V on both ends of L7095.

[reformatt]

Re: Macbook Air 820-00165

Since your PPBUS_G3H is 8.3V and you have no one wire comms to the charger, your SMC is not working. Check for voltages etc around the chip itself (R5100, L5001 for example) then look at Y5110 area to see if the clock is running. Then you would suspect the SMC itself, take off the edge bonding, reflow/reball or replace.

[Instafixx]

Re: Macbook Air 820-00165

Since your PPBUS_G3H is 8.3V and you have no one wire comms to the charger, your SMC is not working. Check for voltages etc around the chip itself (R5100, L5001 for example) then look at Y5110 area to see if the clock is running. Then you would suspect the SMC itself, take off the edge bonding, reflow/reball or replace.

Hello,
Checked the Y5110 but there was no Voltage. Went ahead and replaced U5000 and now we are getting Green/Orange light on the charger. But no fan spin and the macbook still isnt on.

There is Voltage at #1 of Y5110 (SMC_EXTAL) 1.5 Volts (this is after replacing the U5000).

Voltage at Pin#3 of Y5110 (SMC_XTAL_R) is still 0.0Volts.

Should we replace the Y5110 as well?

Also was following repair.wiki and checked the U3510 .

PM_SLP_S4_L is has 0 Volts.
PP3V3_S4 has 1.5 Volts .

[reformatt]

Re: Macbook Air 820-00165

Seems your SMC was the source of the problem now that you have one wire comms. But where did you source the SMC from? It has to either come from another 820-00165 or 820-3437 board and correctly reballed. These can be destroyed by too much heat BTW. Crystals rarely fail. You should see a waveform on a oscilloscope when the board first trys to turn on when power is supplied. If the SMC shuts down after an unsuccessful startup, you won't see any clock here (as far as I remember, would need to double check that).

What is your PPBUS_G3H voltage after replacement? If it's 8.6V, then you should then troubleshoot the PM_SLP_S4 pre-requisites.

[Instafixx]

Re: Macbook Air 820-00165

Seems your SMC was the source of the problem now that you have one wire comms. But where did you source the SMC from? It has to either come from another 820-00165 or 820-3437 board and correctly reballed. These can be destroyed by too much heat BTW. Crystals rarely fail. You should see a waveform on a oscilloscope when the board first trys to turn on when power is supplied. If the SMC shuts down after an unsuccessful startup, you won't see any clock here (as far as I remember, would need to double check that).

What is your PPBUS_G3H voltage after replacement? If it's 8.6V, then you should then troubleshoot the PM_SLP_S4 pre-requisites.

Yes the PPBUS_G3H is 8.6V.
For the PM_SLP_S4_L being missing,
We reballed the U1950 and checked the board, the fan started spinning now and PM_SLP_S4_L. But when we connect the charger the second time, the fan doesnt spin and nothing happens. PM_SLP_S4_L becomes missing again.

Now tried to replace the U1950. But same issue.

What could be the problem?

[reformatt]

Re: Macbook Air 820-00165

Look closely at the edges of the board for evidence of corrosion. This can be easy to miss, so I suggest looking at the sides of components by holding the board at an angle under a microscope. Common areas for this are U1900, U8005, U8130, U5110 and J6100.

Also check rails for voltage initially after power is first applied. If you get Vcore on L7310/L7320 and it disappears (this is classified as a pulse), then your problem is after PM_SLP_S4. Unless you see something obvious on the board, I've found that double pulse on 820-00165 is PCH/CPU related unfortunately.

[Instafixx]

Re: Macbook Air 820-00165

Look closely at the edges of the board for evidence of corrosion. This can be easy to miss, so I suggest looking at the sides of components by holding the board at an angle under a microscope. Common areas for this are U1900, U8005, U8130, U5110 and J6100.

Also check rails for voltage initially after power is first applied. If you get Vcore on L7310/L7320 and it disappears (this is classified as a pulse), then your problem is after PM_SLP_S4. Unless you see something obvious on the board, I've found that double pulse on 820-00165 is PCH/CPU related unfortunately.

Thanks it worked. Reheated and reballed a couple of ICs and the mac works fine now.
1 issue is there that it only runs on a power source. Tried replacing a known good battery but still the same issue. Any help?

[mon2]

Re: Macbook Air 820-00165

measure the voltage to ground of each SMBUS pin (SCL & SDA) on D6950.

[Instafixx]

Re: Macbook Air 820-00165

measure the voltage to ground of each SMBUS pin (SCL & SDA) on D6950.

Voltage at Pin # 1 SCL is ranging from 2.5V to 3.7 Volts
Pin # 2 SDA is 1.6 Volts to 2.4 Volts

These are voltages with only the charger connected.

PPBIS_G3H is about 11 Volts which i think is very high resulting into not charging.

P.S It shows not charging . Doesnt show the Cross sign on the battery.

[reformatt]

Re: Macbook Air 820-00165

PP_BUS_G3H is 11V?? Are you sure about that? Previously you said that it was 8.6V after SMC replacement. So if that is the case, something has happened in between.

[Instafixx]

Re: Macbook Air 820-00165

PP_BUS_G3H is 11V?? Are you sure about that? Previously you said that it was 8.6V after SMC replacement. So if that is the case, something has happened in between.

Yes it was 8V before but after reballing the and heating the ICs as mentioned above, the Macbook switched on but the PPBUS is now 11V. It only runs off the charger. Switches off as soon as you unplug it.

[mon2]

Re: Macbook Air 820-00165

My suggestion is to remove the fuse on PPBUS_G3H. Then confirm the voltage of this rail at the ISL side again.

Review the feedback resistor network that is on this rail. Do not proceed till this voltage is within the normal range. Fault is on the ISL side of the circuit.