What is this error means 4SNS/1/40000000:TB3T-128.000

Sounds like serious hardware problems.

Take it to Apple and ask them to check it out for you.

Allan

That error code indicates issues with your battery. Follow Allan Eckert's advice.

Ciao.

The solution is to be found at the genius bar.

Ciao.

Apple does not publicly divulge the meanings of the error codes, but the applicable procedure for that particular code calls for a shutdown / startup cycle, followed by resetting the NVRAM, followed by replacing the logic board. You can do the first two yourself.

NVRAM reset:

1. Shut down your Mac.
2. Locate the following keys on the keyboard: Command (⌘), Option, P, and R. You will need to hold these keys down simultaneously in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.

After resetting NVRAM or PRAM, you may need to reconfigure your settings for speaker volume, screen resolution, startup disk selection, and time zone information. If issues persist, your Mac's logic board battery (not a portable Mac's rechargeable battery) may need to be replaced. The logic board battery helps retain NVRAM/PRAM settings when your computer is shut down. You can take your Mac to a Mac Genius or Apple Authorized Service Provider to replace the battery on the logic board.

Hi John,

That is what happened to my MBP. I reset NVRAM only to have the same error again. I took it to Apple expecting a battery replacement but was told that it was a problem with the motorboard. After they replaced it I have had no more problems with it.

Allan

Right, I think the NVRAM reset will be a waste of time but it's harmless enough to try.

There is no way to be certain other than to have Apple evaluate your Mac. It may be eligible for a flat rate repair, which would be the most cost-effective solution, but only they can make that determination.