MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

[Stephen]

This is not a flexgate issue.

The lcd turns on and functions fully and fine. When installing or even attempting to install an OS the screen goes black and doesn't turn on. We swapped the LCD with a testing LCD (that works) and it too is also black. After the computer cools down it turns back on and show the screen again and then it goes black when it gets hot. Sounds like a CPU issue to me (since these do not have their own dedicated GPU) but I may be wrong. Has anyone experienced this with this model? Battery is good btw. also I disconnected the battery and it still does the same thing. Also the computer is still on and hot when the screen goes black. Voltage is still going. So I am assuming it is something else. I am curious what it might be? Logic board repair would be easy if we knew this issue but this is a first for us in this model so I am thinking CPU (intel chip) is bad but that could be something along the line that the CPU (intel chip) is fine but something that is connected to it is causing issues.

Any suggestions?

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Side note: Plugged up the computer to an external when it was cold, external monitor displays when in OS install (catalina) when it gets close to installing and (2 mins left before it goes into the Apple Logo it goes black like the computer. The TV now shows no signal and the LCD is black as well. I am suspecting the CPU is the culprit and is getting to hot and turns itself off. The fan is on but it is black. When the computer is cold it turns on showing the LCD and monitor. Any suggestions. Most likely leaning towards a failing CPU but odd it works when it is cold.

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Bumping thread. Any comments?

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Well guess no ideas huh?

[peste]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Well guess no ideas huh?

the video chip is probably in trouble.

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

the video chip is probably in trouble.

You mean the CPU? Because these are single based graphics integrated with the CPU.

[mon2]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Does the vice-versa hold true ?

That is, if you freeze spray / cool the CPU, does the unit remain stable longer ?

Have you reviewed the heatsink compound? Apply a fresh batch and be sure that it is securely keeping the CPU cool enough to operate normally.

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Hey mon2,

I will do that first thing tomorrow when I get back to the shop. I should maybe apply some new thermal and see if that is the case. Chances are it could be overheating and it turns itself off to prevent further problems. I wont know till I get in tomorrow. I will test it out.

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Hey mon2

So installed new thermal paste and cleaned up the CPU. Also installed another SSD with a known operating system that is working and it booted up to the home screen. within 10 seconds after booting up. The computer froze and the screen went black after. Touched the CPU and it is scorching hot. This is after new thermal paste is applied and even the fan was on and it still couldn't cool itself off. It seems the CPU is working but it is getting overheated. Any suggestions?

Also no signs of water damage under the microscope. Seems like a healthy board.

[SMDFlea]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Hey mon2

So installed new thermal paste and cleaned up the CPU. Also installed another SSD with a known operating system that is working and it booted up to the home screen. within 10 seconds after booting up. The computer froze and the screen went black after. Touched the CPU and it is scorching hot. This is after new thermal paste is applied and even the fan was on and it still couldn't cool itself off. It seems the CPU is working but it is getting overheated. Any suggestions?

Also no signs of water damage under the microscope. Seems like a healthy board.

If the board has been reworked near the heatsink without removing it,it could be damaged. Take the heat sink off, heat the pipe above cpu end to 100 degrees or so, if the pipe is still cool at the other end the heatsink is broke.

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

If the board has been reworked near the heatsink without removing it,it could be damaged. Take the heat sink off, heat the pipe above cpu end to 100 degrees or so, if the pipe is still cool at the other end the heatsink is broke.

Awe this is a different angle. I will try this now! Thank you for this idea!

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

If the board has been reworked near the heatsink without removing it,it could be damaged. Take the heat sink off, heat the pipe above cpu end to 100 degrees or so, if the pipe is still cool at the other end the heatsink is broke.

Heated the pipe. It gets hot on the other end so the Heatsink is good.

[mon2]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

Can you confirm that the heatsink is on securely and on top of the CPU surface area? Very important for the heatsink to be properly fastened to allow this component to remove the heat off the CPU.

Also, the heatsink compound is known to be good ? I know that when we do iMAC repairs, for at least the heatsink pads, the stuff @ Digikey is much better material and keeps the video cards cooler than others we have attempted in the past.

We have met them at past trade fairs in Tapei and HK. Our engineers and from personal experience found them to be the best to date to dissipate the heat. However they are more expensive.

https://tglobalcorp.com/

You can buy through Digikey. Apparently they also sell the paste as well.

Can you feel the heatsink getting hotter as the unit runs ? It should.

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

mon2,

yes the heatsink is good and the heat dissapates to the full heatsink. Even with new thermal paste it does fine. The CPU just gets VERY hot still none the less and that heat goes to the end of the Heatsink as well. So CPU is overheating and I am assuming it could be somewhere around that area that needs to be replaced. Maybe a thermal sensor?

[pantsos]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

It seems like a have the exact same issue. Can you try to close the lid and open again, image comes on or it stays off?

I’m my case when image goes off I close the lid and re open and it works for a few seconds and then again goes off.

[Stephen]

Re: MacBook Pro 13" 2017 A1708 Black screen issue (not flexgate)

What you probably have is a flexgate issue. My image disappears even when plugged up externally.