661-8303 / 661-8311 Touchpad + Internal Keyboard connection loss after heating

[minlite]

Hi all, this is my first post. Please bear with me if I didn't get the right board model / issue.

I'm observing this weird issue with my Late 2013 rMBP (A1398) that causes the system to lose touchpad + keyboard connection after some random time. All other USB peripherals continue working. The issue is always resolved after a restart, which leads me to believe something on either the logic board or the top case is going wrong and causing the system to either lose or intentionally terminate the connection to the keyboard and trackpad. The power button keeps working despite the connection loss.

I've tried cleaning the keyboard connector and resetting SMC/NVRAM to no avail.

Any ideas where this might be coming from?

 

[dukefawks]

Could be corrosion on the touchpad connector or flat cable. Any history of liquid damage?

 

[minlite]

Could be corrosion on the touchpad connector or flat cable. Any history of liquid damage?

Sorry for the late reply... Can the corrosion cause this? And no, there hasn't been any water damage.

 

[dukefawks]

Disconnect the trackpad and see if the keyboard still has issues. Fans will run high and system may be slow without it though.

 

[minlite]

Sorry for reviving this thread from the dead... I never got around to fixing it at the time I posted.

dukefawks , I tested that just now and when I turned on the Mac without the trackpad connector in place, it started running slow with fans on their highest speed just like you said, but the keyboard didn't work from the get go, even though its connector was fully in place. Is this by design? Seems kinda silly to keep keyboard from working if the trackpad connector is not in place...

What I forgot to mention in my initial post (or I hadn't discovered this at the time) was that this issue doesn't happen without the charger plugged in. The keyboard and trackpad only die sometime after I plug in the charger, even if the laptop is already at 100%.

I've attached two screenshots of what I see in the system information. Left is with the trackpad plugged in (before it dies alongside the keyboard, sometime after plugging in the charger) and right is without the trackpad plugged in (keyboard doesn't work from the get go)



(Notice how there the system thinks there are two devices on the bus, while there is just one, and the power usage is not displayed correctly)

 

[dukefawks]

It is normal for keyboard not to work when trackpad disconnected. Are you using a chinese garbage charger, they cause all sorts of weird issues.

 

[minlite]

Thanks for the reply. Nope. It's an authentic 85W charger that I bought from the Apple Store.

I also doubt this is an unstable connector issue either because I disassembled the whole MBP a few months ago (down to the keyboard) and reassembled it back. The issue persisted.

I can measure voltages to debug too, but I don't really know which pin should have what voltage...

 

[dukefawks]

Nothing much to debug here. My first thing to do is to swap the trackpad. Yes it sucks, it is under the battery. Lift up battery complete with the metal cover that is over the trackpad.