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AHT: 4SNS / 1 / 40000000: TNOD-127.875

Hello

2 days ago, my computer (MAC PRO nehalem) start to freezing, with no message no console message, and impossible to do anything but forced shutdown (stay pushed on start front button)

I try several maintenance utilities with no success.

I try the official APPLE HARDWARE TEST from the install disk

and I got this error message from the small test :

4SNS / 1 / 40000000: TNOD-127.875


I didn't find anything about it on internet.

What is this, what can I do ??


when I try to do the longer test on AHT. my computer shutdown. so I can't do it.

I'll try again.


Thanks for any informations

Mac Pro, Mac OS X (10.6.8)

Posted on Jul 11, 2011 4:34 PM

Reply
11 replies

Jul 11, 2011 4:43 PM in response to Kappy

Hi Kappy Thanks for your fast answer.


Do have more information about that ?

Is possible to find what's wrong, and to the repair by myself ?

I ask this because I sure the waranty is dead by now.

and this should be expensive in an Apple Repair Center.


last one;

Do you have an idea of what price it should be ?



Thanks again in advance.

Jul 11, 2011 5:25 PM in response to quayman

In Warranty or out-of-warranty, your appointment st the Genius Bar is FREE. They will work with you to determine whether your Mac has a problem, and try to determine what the problem might be.


Once they give you their opinion about what is wrong with your Mac, you are under no obligation to have them fix it. You are still free to have someone else fix, it, fix it yourself, or not fix it, as you choose. Apple wants you to be happy with your Apple products.

May 10, 2013 10:32 AM in response to Etra2

Etra2 -- I took my MacPro to the Apple Store. After a free indepth analysis the verdict was that a Heat Sensor needed to be replaced on the mother board. This is a job for mac service professionals. I would not advise you to attempt to fix it yourself, as they will run further diagnostics to determine which sensor is faulty.


If you can't get to an apple retail store for a genius visit hopefully you have a "Certified" Mac service center close to you, like or similar to a "Melrose Mac" or "Mac Enthusiasts." I would not trust just any computer repair shop. It's well worth the visit to the Genius Bar. The cost to replace the sensor was relatively small compared to the cost of the MacPro. I would suggest getting it looked at right away and not using your computer until it is fixed as prolonged use could cause further, costly damage.

Mar 24, 2016 1:34 PM in response to quayman

The problem here is the temperature sensor on the Northbridge controler.... See here to decode message: http://www.cnet.com/news/how-to-invoke-and-interpret-the-apple-hardware-tests/

System Sensors - Temp - NOrthbridge


I had the exact same problem and found out that one of the rivets that clamps down the heatsink for the northbridge controller had given away:


http://www.xlr8yourmac.com/archives/jul14/071114.html#macproNBoverheating


In my case I just replaced the river and it all went back to normal, but I know the other one may give away in the near future so I'll be monitoring my northbridge temp from now on.

AHT: 4SNS / 1 / 40000000: TNOD-127.875

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