a1706 820-00239-A charging but no 5V Output

[Harryrepair]

Hello community,

what can cause the following problem?

All 4 USBC Thunderbolt connector do recognize the charger and work properly.
But there is no power on 5V Devices like a simple USB memory stick.



Furthermore the device is giving me following failure:

System Sleep Wake failure in EFI

Always i shut the display or the machine wants to launch screensaver it is rebooting and giving me the message after rebooting.


Kind Regards

[mon2]

Re: a1706 820-00239-A charging but no 5V Output

1) check the voltage on L3500, pin # 2. It should be +5v0 (or close to).

2) if not @ +5v0, power down, remove battery and check the resistance to ground on the L3500, pin # 2.

3) Also inspect the small type C paddle boards that mate with the main logic board on the A1706 series. Have seen some bad ones that needed replacement. Often the Type C connectors just wear out or arc with fake adapters. Somewhere on this forum, have shared some ugly pix of a worn out Type C connector that halted an ipad Pro 12" (2020) from working. Issue was just the cable in this case while Apple said it was the logic board and for the client to buy another $1200-$1500 replacement.

[Harryrepair]

Re: a1706 820-00239-A charging but no 5V Output

Thanks for your answer.
I am missing PP5V_S4_X_USBC.

PP5V_S4 is always present.
UPC_X_5V_EN at 3.3V
P5VUSBC_X_PGOOD 0.2-0.6V not stable

What can be the issue?

[Harryrepair]

Re: a1706 820-00239-A charging but no 5V Output

One more question:

How is it possible that PP5V_S4 is always present but the lines resistance to ground is 6ohms?

[mon2]

Re: a1706 820-00239-A charging but no 5V Output

1) PP5V_S4 rail is generated as shown on sheet 72 / 119 of the PDF schematics.

With a resistance of 6 ohms to ground, using ohm's law calculator:

https://ohmslawcalculator.com/ohms-law-calculator

Feed this calculator 5 Volts and 6 ohms, yields 0.833 A.

The rail can support up to 1.58A so it is ok.

2) Since PP5V_S4_X_USBC is missing, power down & remove your battery.

Place your meter in resistance mode (OHMS) and place red lead on pin # L3500 and black lead to ground.

What is the resistance reading ?

3) Using your meter in voltage mode, check the voltage of PPBUS_G3H @ pins 8 & 9 of Q3501 mosfet. This local switching power supply rail accepts the higher PPBUS_G3H voltage and steps it down (BUCK regulator) to generate the missing PP5V_S4_X_USBC rail.

It is possible that the issue is linked to this page # 33 - the mosfet may not be switching or the regulator is not enabled.

4) Check if the regulator is enabled by monitoring the voltage on UPC_X_5V_EN = pin 15 of U3500.

It is interesting to note that this UPC_X_5V_EN logic level is generated by the CDC3215 USB Type C controllers. So respectively, we need to make sure that each of the CDC3215 controllers are working properly. Any of these being damaged can tank this circuit and halt the operation of the logic board.

See here from Piernov:

https://www.logi.wiki/index.php/CD3215_Bootup_Sequence

and this video on CD3215 debugging:

https://www.youtube.com/watch?v=6fEQS1MsZIw

Q: On your USB Type C power supply, do you ever see +20V negotiated by your logic board? What is the value of PPBUS_G3H for your logic board ? If you do see +20V then the CD3215 should be ok which will imply that they should be capable to ENABLE this UPC_X_5V_EN logic level. Post your value for UPC_X_5V_EN. If this signal is ENABLED ok, then the issue is drilling down to the U3500 region.

The +20V USB Type C power delivery contract will only be selected if the CD3215 are not damaged. A bad (Apple power adapter clone) can cause damage to the CCx lines which are required for USB Type C power delivery negotiations. Also a hot removal of a charging adapter which will use 20V can cause such damage. The CCx pins are very close to the VBUS pins on the Type C connector and a sloppy pull-out places the +20V onto the CCx lines and damages the PD controller. New generation of parts allow for tolerances to protect such damage.

[Harryrepair]

Re: a1706 820-00239-A charging but no 5V Output

Thank you mon2 for spending so much time with helping me.

Before i go on, here is a short explanation about the history of this macbook.
it was liquid damaged. I took a spare board and changed

1.SMC
2.U7800 SN650839 (Power Management Controller/ is this the pch?)
3.isl95828 (CPU Controller?)

After this work the macbook came back working and usable.
Charging on every Port with 20.3V.
I mention that all cd3215 are ok so far.


PROBLEM 1:
No one port recognizes any 5V source, i tried with a simple USB Drive on usb-c adapter.
I checked this adapter-USB Drive combination on a working macbook before.


PROBLEM 2: (possibly a result of problem 1?)
Instead of hibernating / switching to wallpaper mode AND when in standby (Display shut)
the machine does reboot by itself and giving me the ERROR :

Sleep/Wake failure in EFI

All other functions were OK.



From this point i did :

1. new (known working) BIOS with ME clean (old SN copied)
2. "POST TOPIC" Found this 5V Line (U3500,UB700) with problems.


Today i took out both isl95870 USB controller and 3 resistors which were found with about 17ohm instead of 2.2

R3501 / R3506 / RB706

Why was on RB701 PIN2 PP5V_USBC_T_VCC passing 5V?


PP5V_S4 has now 130ohm to ground

UPC_X_5V_EN was at 3.3V

BUT

P5VUSBC_X_PGOOD was only 0.2-0.6V

I want to put in new isl`s and resistors but ran out of spare parts.
I think something is pulling down PP5V_S4

[mon2]

Re: a1706 820-00239-A charging but no 5V Output

Try the SMC reset = step # 3 here:

https://softwaretested.com/mac/macbo...%20work%20fine.

[Harryrepair]

Re: a1706 820-00239-A charging but no 5V Output

Today i changed the mentioned 3 resistors and both isl U3500/UB700.
5 V is back.

No i get the message that computer is disabled.
Because i changed the bios chip?

[mon2]

Re: a1706 820-00239-A charging but no 5V Output

Hi. See here:

https://discussions.apple.com/thread/250159484

Good idea to ask in the BIOS forum as well.

[Harryrepair]

Re: a1706 820-00239-A charging but no 5V Output

i changed the bios chip back to original. Before it was a donor with ME region free and SN number copied.
Now the machine is running with 5V Output.

Sleep Wake failure is still present, so i had 2 different problems.

Everytime the lid is closed, this macbook reboots by itself.

[mon2]

Re: a1706 820-00239-A charging but no 5V Output

Try a SMC and PRAM reset.