A1398 - 820-3663-A - not charging

[obelix24]

I got macbook pro A1398 15" from my friend. He told me that he changed battery and macbook stopped charging.

Boardnumber : 820-3662-A

I've checked and when i connect charger it's recognized by MacOS but there is no light on charger and it's not charging battery (i've tried multiple chargers still the same behaviour), i've also tried 3 different magsafe ports.

I've check U7100 and replaced it multiple times (from other donor boards that i have) (i've tried probably 7 different U7100) - i've also checked current resistors around this ISL (R7151, R7152, R7121, R7122) they're all good.

I was able to get one time led on charger but after maybe minute it turned off and stay so ...

I've checked with thermal camera and i can see that U7100 is still getting warm (but i guess this is normal and this is chager IC)

Also i noticed that C7105 - pin CHRG_DCIN is stable 20,3V when charger is connected but no light on charger.

When i was checking with thermal camera around the board i noticed that one resistor (R5413) is getting warm but i've checked it and it have correct diode mode reading 0,74 pin 2 and OL on pin 1, also it's resistance is 33kOhms a it should be according to schematics.

Any idea what this strange behaviour can cause ?

Is it possible that U5000 is bad ?

[reformatt]

You are on the wrong track. If there is no light on the charger, then the SMC will not enable charging. You would start with the one wire circuit (U7000 and U7001). SMC_BC_ACOK comes from U7100 and this must be high to allow Vcc for U7000. SYS_ONEWIRE comes from the SMC and is used to communicate with the charger and establish it's wattage etc. SMC needs that info to determine whether charger is suitable or not, so lack of signal here means no charging. U7000 is an over voltage protection device so you should see identical signals on both input and output. If that all checks out, then you would look at the SMC itself.

[obelix24]

I've checked U7000 and U7001 (diode mode readings are ok)
When power is connected U7000 and U7001:
ADAPTER_SENSE - 2.8V
SYS_ONEWIRE - 2.8V
SMC_BC_ACOK_VCC - 3.4V
SMC_BC_ACOK - 3.28V
PP3V42_G3H - 3.42V

Diode mode readings U7000 and U7001:
ADAPTER_SENSE - 0.621
SYS_ONEWIRE - 0.677
SMC_BC_ACOK_VCC - 0.586
SMC_BC_ACOK - 0.552
PP3V42_G3H - 0.324

[mon2]

Use ipa to clean the MagSafe contacts on the charger connector.

[obelix24]

i tried cleaning, different connector, different charger... still no light

[mon2]

Follow this flow chart:

G3 to S3 State for Ivy Bridge Haswell and Broadwell - LogiWiki

[obelix24]

according to this SYS_ONEWIRE should be 3.4V but i have only 2.8V
PPBUS_G3H - 12.58V

I'll try to replace U7000

[mon2]

Wait..the voltage is low and is created by U7001.

Measure the voltage to ground of pin 4 on U7001.

Most likely, U7001 needs to be replaced.

[obelix24]

pin 4 on U7001 -
SMC_BC_ACOK_VCC - 3.418V

i tried to replace U5000 and U7000 but now difference.

[obelix24]

i tried to replace U7001 but still the same .... the SYS_ONEWIRE is created by U5000 no ?

[mon2]

Remove all power. Measure the resistance across R7029. What is the value in ohms?

Yes, U5000 is the bus master for this communication channel but the Vcc voltage for U7000 is of concern. It is possible that you are measuring a lower than the peak voltage if the communication line is switching. That is, an oscilloscope will be the true test tool to use here. Another tool is a logic analyzer.

Replace U7000 if you have a known good one for testing.

[obelix24]

they all looks ok.

I noticed one this when i put everything back to case macbook doesn't turn on as before ....

I've returned original U5000 (the other one i've used from donor a1466 - same numbers) during replacing i probably damaged X29 as now macbook turns on but fans are on full speed.
Is this connected to Q6060 ?

But there is still no light on charger ... I was thinking if it's not caused but not original battery but i don't think as the light is not there even if battery is not connected and it should be there.

[obelix24]

is U5000 replecable on A1398 ? i tried from differrent 15" and macbook is not turning on and fans are going to max speed but not immediately but it take some time.

[obelix24]

I found that IC for temperature should be probably U5823
is it correct ? Is it most probably the cause of full fan ?

[obelix24]

After some digging i found out that left fan is faulty and have faulty ic on fan cable.

i'm still trying to find why there is no light on charger.

[obelix24]

ok so to me it looks like problem is with U5000 (but as i've tried to replace it and the macbook want start it looks like this U5000 is not replaceable ?)