820-01598 Crush damage - 20V 0.0035A

[AJ847.63e]

Hi All,

I'm trying to fix a 2019 macbook pro 13" 820-01598.

I'll cut straight to the chase, if you need to see more history see below. Can the system boot without U5700? The caps & resistors surrounding U5700 and u5700 itself have been removed despite being told by it's original owner no one has opened this machine. Are these no stuff which has not been marked in the schematic/boardview?

History is the previous owner left it on the roof of his car and drove off driving over the laptop cracking the screen, trackpad and whole chassis. He says he did not touch it after this incident just threw it on marketplace where I bought it. When I checked it out there were no signs of life, no image, could not see any backlight, no track pad click and no caps lock light. I opened it up it seemed like I was the first one in there. It seemed like the system was actually still on, no fan spin but the whole board was quite warm not hot hot but pretty warm so it definitely seemed to be powered on. I tried holding the power button to turn it off but that seemed to do nothing. I disconnected the battery and hooked up my amp meter and it looks like the board is taking 19.93V 0.0035a.

I disconnected everything than powered the board and the board only. Again I was still only getting 19.93V 0.0035a. I noticed on the protocol it came up as Samsung. I switched over to my 29w Apple charger but that only changed the protocol to PD MTK everything else stayed the same. I than connected the board back in the chassis and hooked everything up and the board went up to 14.688V 0.349A and started fluctuating between that and 0.36A than briefly shot up to 1.126A and back down to 0.58A than back up to 1.36A than back down to 0.264 than I removed the power and re connected and now no matter what I do now I only get 19.93V 0.0035A. Even tried removing everything and powering only the board still 19.93V & 0.0035A.

I went to go check the power sequence diagram so I checked PPBUS_G3H on CD760 & that is when I noticed all the caps & resistors surrounding U5700 and u5700 itself have been removed. I have not checked anything else as I'm assuming there's no point if U5700 is missing?

Thanks for your assistance!

[mon2]

Re: 820-01598 Crush damage - 20V 0.0035A

Appears to be a no-stuff @ U5700 - does your logic board look like the attached pic ?

[piernov]

Re: 820-01598 Crush damage - 20V 0.0035A

U5700 has BOM option LOADISNS, not populated on production boards.

[AJ847.63e]

Re: 820-01598 Crush damage - 20V 0.0035A

Few, had me worried thanks guys! With these should connecting just the charger to the board alone power them up? I'm worried there's damage in the accessories (trackpad, screen, battery) so I want to try confirm the board works before I go adding more variables not to mention things that are likely damaged. Just seems strange that we shot up so high just once, when resetting the adapter it went back down to 35 ma and can't get anything since that initial blip. Is their any common damage areas with crush damage or should I just go down my power sequence diagram and see what's missing?

Thanks!

[AJ847.63e]

Re: 820-01598 Crush damage - 20V 0.0035A

Appears to be a no-stuff @ U5700 - does your logic board look like the attached pic ?

Thanks, Yes that area looks identical.

[AJ847.63e]

Re: 820-01598 Crush damage - 20V 0.0035A

Somethings not right here. Just checked for PPBUS_G3H on CD761 and I'm only getting 0.5v. Ohms measurements in the millions range so there's no short on the line. I'm thinking the boards not being told to turn on despite the charger being hooked up.

[mon2]

Re: 820-01598 Crush damage - 20V 0.0035A

This is a USB Type C powered logic board so the CCx lines on the Type C connector are used between the logic board and the external power delivery capable adapter (Apple is recommended). Check the power rating for this system to use the same.

Once the two parts are mated, the power adapter and the logic board will exchange power contracts and the adapter will be required to supply the 20V rail to power this unit.

1) Post the voltage @ PPDCIN_G3H.

2) PPBUS_G3H @ F7000 without battery but with external power adapter.

3) PPBUS_G3H @ F7000 with battery.

From my (limited knowledge) of the Samsung products, funky D+ / D- lines with assorted resistor voltage dividers are used to dial up the proper voltages for the target Samsung units. The results from the Samsung devices is not relevant for the Apple devices which are USB Type C Power Delivery designs.

Just saw your new post...

Confirm the input voltage is ok. Check status of fuse F7000.

[AJ847.63e]

Re: 820-01598 Crush damage - 20V 0.0035A

This is a USB Type C powered logic board so the CCx lines on the Type C connector are used between the logic board and the external power delivery capable adapter (Apple is recommended). Check the power rating for this system to use the same.

Once the two parts are mated, the power adapter and the logic board will exchange power contracts and the adapter will be required to supply the 20V rail to power this unit.

1) Post the voltage @ PPDCIN_G3H.

2) PPBUS_G3H @ F7000 without battery but with external power adapter.

3) PPBUS_G3H @ F7000 with battery.

From my (limited knowledge) of the Samsung products, funky D+ / D- lines with assorted resistor voltage dividers are used to dial up the proper voltages for the target Samsung units. The results from the Samsung devices is not relevant for the Apple devices which are USB Type C Power Delivery designs.

Just saw your new post...

Confirm the input voltage is ok. Check status of fuse F7000.

Thanks, I'll check the 3 requested lines and get back to you tomorrow. 20V is being negotiated from the charger.

Just thought I should add I'm using a alogic USB C power adapter: https://www.costco.com.au/TVs-Electr...0-ANZ/p/109208
Yes, yes I know never use generic chargers. I wanted to get a apple one but they were out of stock, and the genius bar guy told me these are fine. Guess they use the Samsung PD specification rather than the apple one which explains why I am getting the samsung PD protocol. But than I did try my 29W apple one and that is doing the same thing, but that's only 29W so it may be too low for the machine to boot?

Thanks again, I'll get the measurements and post back tomorrow.

[mon2]

Re: 820-01598 Crush damage - 20V 0.0035A

The referenced 100W PD capable Type C GAN adapter should be fine for your target machine.

There are a number of low cost PD bus analyzers (ST, Cypress, etc.) that can monitor the CCx lines and can display the power contracts being negotiated. Most of these tools are < $ 100 USD these days.

[piernov]

Re: 820-01598 Crush damage - 20V 0.0035A

No need for fancy tools, you just need a decent USB-C ammeter. However you absolutely need a good USB-C power brick and cable of correct power rating. I'd recommend getting genuine Apple branded ones, you never know what the knockoff did wrong. This machine requires at least a 61W, but better get an 87W or even 96W so you can use it on all USB-C MacBooks.

[AJ847.63e]

Re: 820-01598 Crush damage - 20V 0.0035A

This is a USB Type C powered logic board so the CCx lines on the Type C connector are used between the logic board and the external power delivery capable adapter (Apple is recommended). Check the power rating for this system to use the same.

Once the two parts are mated, the power adapter and the logic board will exchange power contracts and the adapter will be required to supply the 20V rail to power this unit.

1) Post the voltage @ PPDCIN_G3H.

2) PPBUS_G3H @ F7000 without battery but with external power adapter.

3) PPBUS_G3H @ F7000 with battery.

From my (limited knowledge) of the Samsung products, funky D+ / D- lines with assorted resistor voltage dividers are used to dial up the proper voltages for the target Samsung units. The results from the Samsung devices is not relevant for the Apple devices which are USB Type C Power Delivery designs.

Just saw your new post...

Confirm the input voltage is ok. Check status of fuse F7000.

Interesting, if I use the alogic charger I get nothing at all 3 points you asked me to measure. I disconnected that and hooked up my 29W apple charger and now were drawing 14.779V 0.0143-173a.
PPBUS @ F7000 = 12.6V without battery.
PPDCIN_G3H @ F3001 = 14.7 and steady not fluctuating

Looks like I need to take that charger back and arrange a refund. .

[AJ847.63e]

Re: 820-01598 Crush damage - 20V 0.0035A

FYI I'm using the FNB48 amp meter which does tell you the protocol and also the D+ & D- lines which are 3.29 1-9 fluctuating on the positive and 3.299 on the negative.

Interesting, I went and bought a original Apple 96W charger and now were pulling 20.568V @ 0.0372A. The protocol is listed as QC2.0 20V.
PPBUS_G3H @ F7000 = 12.56V and steady.
PPDCIN_G3H @ F3001 = 20.54V.

I have not checked PPBUS_G3H with the battery. I want to avoid plugging in the battery if I can. The connector on these is so fiddly and I'm worried I'm going to short something. Plus the trackpad is bowed and the battery's probably got internal damage so I'm not too keen to play around with it if I can avoid it.

I'll go through the power sequence table and see what rails missing and report back.

Thanks again for the assistance!

[AJ847.63e]

Re: 820-01598 Crush damage - 20V 0.0035A

No need for fancy tools, you just need a decent USB-C ammeter. However you absolutely need a good USB-C power brick and cable of correct power rating. I'd recommend getting genuine Apple branded ones, you never know what the knockoff did wrong. This machine requires at least a 61W, but better get an 87W or even 96W so you can use it on all USB-C MacBooks.

For the power sequence diagram are those rails sequential? IE The one above it has to be present for the lower to be? I'm about half way down the list now and they all seem present. One thing I have noticed though is I'm contently having to reset my charger every 10 minutes or so as it drops down to 35ma and none of the rails are present so it seems to be going into a protection mode or something. Removing the adapter from the wall and reconnecting resolves this and brings it back up to 380ma or so.

This is looking more and more like a corrupted T2. Is there a way to restore this without another mac? I know you can use apple configurator 2 but I do not have a working mac.

Either that or I'm thinking I should hook everything up including the battery and see if the power draw changes at all. I remember TCRS saying in a video these won't boot without a battery and a screen is that true? This screens shattered to hell so the chances of it being detected are pretty slim, and it's not worth ordering a replacement just to find the boards dead.