Problems with start-up, crashing and external devices

Question

Problems with start-up, crashing and external devices

I'm having a number of issues with my MBP. In short, there are major issues with start-up which compromise the machine's reliability :-( I hope someone might be able to help!

If I Shut Down the computer and want to start it up again, I have to press the power button (or another key) lots of times, wait about five minutes etc. before it does so. It won't ever start up on the first try. Similarly, if I press 'Restart', the computer will power off but not start up again. When it does start up, I usually get a 'this computer was restarted due to a problem' message and then the error report starts with 'panic(cpu 2 caller 0xffffff7f93b33399): "UPSB(MacBookPro15,2): thunderbolt power on failed 0x15788086\n"@/AppleInternal/BuildRoot/Library/Caches/com.apple.xbs/Sources/IOPCIFamily/IOPCIFamily-370.100.21/IOPCIBridge.cpp:1398'
Sometimes if I remove an external device (e.g. USB hub or printer), the computer will freeze up and just power off randomly. Then point 1 happens again.
Sometimes if I try to use the computer too quickly after I have logged in (before everything has loaded I guess), the computer will freeze and power off randomly too. Then point 1 happens again.

Things I have tried: I have reset the NVRAM and SMC. I have erased the hard disk and reinstalled the OS. The problem still persisted at this stage, even when the computer was blank with just the OS installed.

Is there anything else I can try before sending it in to Apple?? It's obviously a pretty new machine and the problem has been going on for a few months (before updating to Catalina) but with everything that's going on with coronavirus I can't really take it to an Apple Store right now. Has anyone had a similar problem??

Thanks in advance!

MacBook Pro (13-inch, 2018, Four Thunderbolt 3 Ports)

Processor: 2.3 GHz Quad-Core Intel Core i5

macOS Catalina Version 10.15.15

MacBook Pro with Touch Bar

Posted on Jul 2, 2020 1:06 AM

Reply

Answer 1

Top-ranking reply

HWTech

Level 9

60,302 points

Jul 2, 2020 7:21 PM in response to cedarmusic101

You've done some great troubleshooting there! I'm so glad you qualified that the "clean" reinstall of macOS did not include restoring or migrating from a backup or installing third party apps.

Maybe you can post the complete Kernel Panic reports here, but from what you have posted I think you may have an issue with the USB-C I/O ports, or the Logic Board, or one of your external devices due to the "Thunderbolt power on failed" in the Kernel Panic and the fact it occurs when connecting/disconnecting external devices. Try connected only a single device directly to the Mac to see if you still get a Kernel Panic with the clean install of macOS. Try the device with each USB-C port especially one on each side. Try each of your devices individually and on each port.

If your device requires an adapter, then try using a different adapter with the device preferably a different brand adapter. Also make sure to use a different data cable if it is removable from the device.

If you have access to another Mac you may want to try using Apple Configurator 2 to revive and/or restore the firmware on the T2 security chip. I don't know if this will help in your situation as it is not listed as a symptom:

https://support.apple.com/lv-lv/guide/apple-configurator-2/apdebea5be51/mac

If the issue occurs with more than one device, then it would indicate a hardware issue with the laptop itself.

Reply