MacBook Pro (A1502 / 820-3476-A) - No orange/green light and no power

[techrepairheide]

Hello again,

got an MacBook Pro from 2015, model A1502 and motherboard version 820-3476-A.

Device died over night on charger.

Currently I did the follow things:

1. Checked visuell the board, test with another MagSafe-Charger and with another DC-IN-board too
2. Measured 16,5V on PP18V5_DCIN_FUSE but 0V on ADAPTER_SENSE and 0V on PP_3V42_G3H and 0V on PPBUS_G3H but 16,5V goes to U7090
3. Because of corrosion and bad resistor values I changed these components: U7090 / C7094 / C7095 / R7095 / R7096 / L7095 / C7099 -> But further 0V on these rails
4. I have a water damaged board here with orange/green pulsating and no power and I got the components from here. I exchange the parts from other board and light is coming up -> So these components are not the problem
5. Measured O.L on the resistors for feedback rail on U7090 -> Built jumper -> 1,25V present, 3,3V ADAPTER_SENSE present now and PP3V42_G3H is with 3,32V present too. PPBUS_G3H shows now 12,27V and not 12,56V that indicates the SMC turned on
6. Still no charging light and power up and with PPBUS_G3H with 12,27V I know, that the SMC is not enabled so I measured 3V on SMC_WAKE_L and the entry on SMC is negate so I think this is right because SMC_WAKE_L must be a high signal "1" but goes in "0" to work properly. I´m right? Or should it be 0V here?
7. Measured SMC_RESET_L on U5110 and got 3,29V on this rail. SMC_TPAD_RST_L and SMC_ONOFF_L with 3,29V too and I think that is correct too but I´m a little bit confused if the negate points mean it converts signal to "0" or low or it means it want low (With short to ground)
8. Did a SMC reflow and issues still there

So now I don´t know how I proceed with this. What are the next steps?

I ordered matching stencils for MacBooks/SMC because I think next thing to do is reball SMC and then exchange with knowing good SMC.

Can I measure some other things, which I missed or overlooked?

Thanks in advance for your time and advices.

[mon2]

If there is a _L suffix in the netname then this means the signal is ACTIVE LOW. Meaning that when the signal is LOW, the task is active. For example, RESET_L means when the signal is LOW, the target is RESET. Respectively, after the work is done, this signal must be the opposite state of HIGH else the part will remain parked in RESET mode. Then the board is stuck.

Check the voltage to ground of the SMBUS lines which are used by the battery and the ISL controller for the PPBUS_G3H. If the SMBUS line(s) are stuck, then the PPBUS_G3H voltage will not be boosted.

[techrepairheide]

Hello,

thank you for your explanation. That sounds logic.

I measured the full ISL inputs and outputs:

PIN ILS	Value (Board with liquid damage - no power, but charger light orange and seldom green) in Volt	Value (Board need to repair with no light/power) in Volt
1	0	0
2	16,75	16,7
3	4	4
4	3,1	3,1
5	1,27	1,27
6	3,2	3,2
7	Pulasting between 0,2-0,9	Pulasting between 0,2-0,9
8	2	2
9	0	0
10	3,2	3,2
11	3,2	3,2
12	3,2	3,2
13	3,2	3,2
14	3,2	3,2
15	0	0
16	12,56	12,24
17	12,59	12,24
18	12,59	12,24
19	5,4	5,4
20	5,5	5,5
21	0,67	0,2
22	Ground	Ground
23	12,54	12,24
24	13,5	12,64
25	17,4	17,0
26	16,2	16,2
27	16,4	16,4
28	16,4	16,4

All I see is, that the big difference is the 12,56V to 12,27V and can´t see any inputs or outputs with 12,56V which could give me a notice maybe mosfet or transistor don´t switch right. Where exact in this circuit is the 12,56V generate or should generate? I read it´s an indicator for not enabled SMC. SMBUS Voltage for clock and data are present.

[mon2]

Study this flow chart:

https://logi.wiki/index.php/G3_to_S3..._and_Broadwell

[MobileXT]

You need to troubleshoot first the PP_3V42_G3H power rail. This power rail responsible for the green/orange light on the MagSafe charger and the SMC.

[techrepairheide]

Study this flow chart:

https://logi.wiki/index.php/G3_to_S3..._and_Broadwell

Did it before up to state "PM_SLP_SUS_L":

- PP_3V42_G3H is present with 3,32V
- Checked Clock-Signals with Oscilloscope -> Working
- All Signals and Voltages are present until state SMC_PM_G2_EN there is 0V but SYS_ONWIRE has 3,32V and with that I get all lines until ADAPTER_SENSE and there is also 3,3V but no orange or green light
- PP3V3_S5_SMC_VDDA has 3.32V too so I though it must be a issue between SMC and charging-ic.

Changed ISL three times to ensure good solder but with new one I got 16,5V on PPBUS_G3H ? Removed Q7130 to isolate it but still 16,5V and not like before 12,27V.

This is driving me nuts.

[mon2]

PP_3V42_G3H

PP3V42_G3H is @ 3v32? This is too low.

What is the voltage to ground of pin # 3 on D7005?

Remove all power. Meter in resistance mode. Measure the resistance of R7095 and R7096. Confirm the measurements match the schematic values.

Confirm the resistance to ground of PP3V42_G3H to be sure there is not an excessive load on this low current rail which will cause a voltage drop.

Assuming all of the above is correct, replace U7090 as this rail should be a stable 3v42.

Be sure you are using the original (OEM) adapter for this box. Power rating is correct for this adapter to power this laptop?

[techrepairheide]

PP3V42_G3H is @ 3v32? This is too low.

What is the voltage to ground of pin # 3 on D7005?

Remove all power. Meter in resistance mode. Measure the resistance of R7095 and R7096. Confirm the measurements match the schematic values.

Confirm the resistance to ground of PP3V42_G3H to be sure there is not an excessive load on this low current rail which will cause a voltage drop.

Assuming all of the above is correct, replace U7090 as this rail should be a stable 3v42.

Be sure you are using the original (OEM) adapter for this box. Power rating is correct for this adapter to power this laptop?

- D7005 on all three pins ~16,5V and diode measured in good condition in diode-mode (flow only to one side)
- U7090 replaced already. Cause 0V on 3,42V rail, but problem was corrosion under resistor-pad so I build a jumper. After that got 3,32V, replaced U7090 in hope getting 3,42V again but absolutly same voltage
- Already removed R7095 and R7096 and exchanged because of corrosion. Double checked and measured resistance with resistors off-circuit with 349kohm und 209kohm like schematic and on-circuit 50kOHM and 149kohm and on-circuit to ground ~150kohm
- Tried to measure PPBUS_G3H in diode-mode on PIN2 F7140 -> black probe = ground / red = Fuse and ohm goes from ~150ohm up to O.L and when I switch probes, it goes back to 150ohm... Resistance mode says ~460kohm and decreases slowly and increases again when its und 1kohm
- Using original MagSafe 2 Adapter with 85W

I´m not sure if maybe a mosfet/dual-channel mosfet shorted to, because I don´t know where suddenly the 16,5V are coming from on PPBUS_G3H.

[mon2]

PPBUS_G3H in diode-mode on PIN2 F7140 -> black probe = ground / red = Fuse

Reverse the leads. Red probe to ground; black probe to the point to test. No power to the board during diode or resistance mode testing.

[mon2]

D7005 on all three pins ~16,5V

This is incorrect. Remove all power. Meter in diode mode. Red meter probe on pin # 1; black meter probe on pin # 3. Meter should conduct. What is the measured value?

Reverse the leads; meter should block.

Repeat with pins # 2 & # 3. Same values apply here. If you measure 16v5 on each leg then this dual diode is defective and must be replaced.

[techrepairheide]

Tested with no power.

On diode with red probe on PIN1 or PIN2 and black probe on PIN3 I measure 217-220ohm and nothing/no conduct with reversed probes neither on PIN1 nor PIN2. The voltage is slighty different, one side 16,70-16,9V unstable and PPBUS_G3H_R on Diode 16,5V.

PPBUS_G3H in diode of course with red probe on ground and black probe on testpoint -> 158ohm.

During measure it feels like I load up a mosfet or a capacitor

[mon2]

What is the resistance to ground of L7095?

What is the voltage to ground of DCIN_ISOL_GATE?

[techrepairheide]

Resistance to ground of L7095 -> PIN1 = ~50kohm / PIN2 = ~70kohm and ~312ohm in diode-mode.

DCIN_ISOL_GATE = 6,7V and I think that is correct too, because auf p-channel mosfet which voltage on gate must be lower than source and then it let it trough.

Who is the culprit to get 16,5V instead of the properly 12,27V (with smc off/no boost to 12,56V) on PPBUS_G3H after changing charging-ic ISL? I don´t get it.

[mon2]

Double check your reworked area of U7090. This voltage must be a stable 3v42 @ L7095.

The rest of the issues may resolve once you have this rail at 3v42. The SMC is responsible @ U5000 to boost the PPBUS_G3H voltage.

[techrepairheide]

Hello again,

actually, one of my problem is the dual-channel mosfet Q7130. Without the mosfet I get 0,25V on PPBUS_G3H and not anymore 16,5V.

It's a K03P0 RJK03P0DPA and I have continuity on MOS1 in both ways between PIN2/3/4 (D1) and PIN9 (S1/D2). Tried to close gate or open circuit with black probe on PIN1 and red on drain/source but nothing change. MOS2 with schottky barrier diode works fine with 150ohm from PIN5/6/7 (S2) to PIN9 (S1/D2) and no continuity in the other way. Gate on PIN8 open and close the circuit. So I think this mosfet is shorted and the culprit or one of the culprits, why PPBUS_G3H doesn't show 12,27V and instead 16,5V. Did I measure it right?

Maybe ISL is the culprit too.

Is there a similiar mosfet with same specs/function that I can buy on the internet? This specific same model is hard to find, only in AliExp.

[mon2]

Do not power up if parts are missing on the board. Otherwise, the logic board is at a risk of permanent damage. For example, on a switching regulator, you have a high side and low side mosfet where each will turn on/off as driven by the switching regulator IC to dial down the high voltage from the power adapter (~20v) to say 1v0 (CPU, etc.). It is vital that the low side mosfet (the one that lowers the voltage) be present else the high voltage (only) from the power adapter will kill the CPU immediately.

I get 0,25V on PPBUS_G3H and not anymore 16,5V.

This is fine. PPBUS_G3H should never be 16v5. In normal cases, the PPBUS_G3H should be 12v6.

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

For a replacement for RJK03P0DPA, the following looks to be a valid replacement:

https://www.mouser.com/ProductDetail...RxJgq5ow%3D%3D
* USD funds

Vishay / Siliconix part # SIZF906BDT-T1-GE3


From Digikey:

https://www.digikey.ca/en/products/d...A4gKIDMIAugL5A
* USD funds


Suggested replacement datasheet: