Macbook Pro Mid-2015 (A1398) Boot Loop

[celo]

Macbook keeps rebooting during apple logo screen. When problem started, it would boot Ok once every 5-6 tries but then reboot shortly after login (5 mins). Have already tried resetting PRAM + SMC. Trying safe mode doesn't seem to reboot during boot ... but gets struck at the end of the progress bar and never goes into safe mode. Recovery mode seems to stay up longer but at some point reboots as well trying to download / install new OS.

1 - Changed SSD to a new one - same problem happens.
2 - Disconnected battery - same problem happens
3 - Disconnected keyboard connection - same problem happens
4 - Disconnected trackpad ribbon - OS boots every time (although system run slow). Note: keyboard won't work with trackpad disconnected so connected a USB keyboard.

With everything else connected and trackpad ribbon still off, system boots as step 4.

Additional note: this problem started when the battery was swollen. When the system did boot, battery doesn't seem to charge and if I disconnect the power cable, systems shuts off. I didn't replace it right away. I had a battery from an older model where the battery is less than 1 year old (has 120 cycles) so I replaced it. Battery still doesn't seem to be charging and won't work without power cable. But when the system was up I did a battery check and it checked good (coconut app and system info).

I am replacing the trackpad ribbon and possibly the trackpad in a couple of days. Just wondering if anybody has seen this and if it could be something else (like bad SMC).

 

[MacInWin]

Welcome to the forum.

I don't have any other advice for you, but did you replace the swollen battery? Swollen batteries can be dangerous and should be replaced and properly disposed of.

 

[celo]

Welcome to the forum.

I don't have any other advice for you, but did you replace the swollen battery? Swollen batteries can be dangerous and should be replaced and properly disposed of.

Yes. The battery I replaced it with was one I bought ne, used for a year, but was sitting in the old laptop for 2 years.

 

[celo]

New trackpad cable doesn't fix the problem. Waiting for trackpad to arrive tomorrow and try that out.

 

[Rod]

There does seem to be a particular range of odd power issues with the 2015 MBP. I just traded mine in on an M1 pro MBP 14" after nursing mine through the last 6 months or so with an erratic shut down issue.

It would simply shut down for no apparent reason during use or sleep and would occasionally allow reboot and login then shut down again after a few minutes or shut down during reboot and refuse to boot to the login window at all. Usually it would boot after an hour or so, sometimes not.

Obviously I checked for power and heat issues as the battery had been replaced shortly before this started to happen. Had all of the internal circuitry checked (similar process to your own) all to no avail.

Eventually at the recommendation of another member of these forums I installed a system utility called Amphetamine and it's "helper" app with good results.
I'm not saying that this will necessarily be helpful in your case, it was in mine with the minor drawback that I could not turn the device off, which I rarely did anyway. It's free on the App Store so maybe worth a try if you can get your device up and running long enough?

 

[celo]

There does seem to be a particular range of odd power issues with the 2015 MBP. I just traded mine in on an M1 pro MBP 14" after nursing mine through the last 6 months or so with an erratic shut down issue.

It would simply shut down for no apparent reason during use or sleep and would occasionally allow reboot and login then shut down again after a few minutes or shut down during reboot and refuse to boot to the login window at all. Usually it would boot after an hour or so, sometimes not.

Obviously I checked for power and heat issues as the battery had been replaced shortly before this started to happen. Had all of the internal circuitry checked (similar process to your own) all to no avail.

Eventually at the recommendation of another member of these forums I installed a system utility called Amphetamine and it's "helper" app with good results.
I'm not saying that this will necessarily be helpful in your case, it was in mine with the minor drawback that I could not turn the device off, which I rarely did anyway. It's free on the App Store so maybe worth a try if you can get your device up and running long enough?

Will definitely give it a try. Thanks.

I thought I had it isolated when I disconnected the trackpad cable. But the more I've read, the more I knew that could easily and would likely not be the issue.

 

[celo]

There does seem to be a particular range of odd power issues with the 2015 MBP. I just traded mine in on an M1 pro MBP 14" after nursing mine through the last 6 months or so with an erratic shut down issue.

It would simply shut down for no apparent reason during use or sleep and would occasionally allow reboot and login then shut down again after a few minutes or shut down during reboot and refuse to boot to the login window at all. Usually it would boot after an hour or so, sometimes not.

Obviously I checked for power and heat issues as the battery had been replaced shortly before this started to happen. Had all of the internal circuitry checked (similar process to your own) all to no avail.

Eventually at the recommendation of another member of these forums I installed a system utility called Amphetamine and it's "helper" app with good results.
I'm not saying that this will necessarily be helpful in your case, it was in mine with the minor drawback that I could not turn the device off, which I rarely did anyway. It's free on the App Store so maybe worth a try if you can get your device up and running long enough?

So I was able to install the application you mentioned and yes, the macbook does not reload now. This is so bizarre. Still takes like 10 times to boot. Still scratching my head at what it could be. Might just have to replace the logic board.

Interestingly the battery now shows 0% and bad with coconut app. It happened before I installed the Amphetamine app though. Might try another battery.

Thanks