Northbridge temperature sensors going crazy!

Hey there!

I'm on a Unibody A1342 MacBook Core 2 Duo 2.4 13" (Mid-2010) that I've modified with extra RAM, a new HDD, and a new battery. It's been running on El Capitan for about a year, with no hardware changes or OSX changes.

The fan started acting up as of late. I tried all the usual solutions: killing processes in Activity Monitor that could be overloading the CPU, reseting PRAM and SMC, even taking the back off and cleaning with compressed air and lubricating the fan axle, but to no avail. I upgraded to Sierra and the problem persisted. I use DiskDrill to monitor temperature and the CPU never went above 35C so I didn't think it was a temperature problem.

I downloaded TG Pro to more accurately check out my temperatures to make sure, and was surprised to find that almost all the Northbridge sensors were reporting incredibly high temperatures, or cutting out sporadically and reporting nothing at all. Everything was normal except Northbridge TN0S, TN1E, TN1F, TN1S, and the second core sensor. These all would spike over 90C, causing my fan to go crazy. This must be what has been making my fan run so loudly at 6200RPM. After continuing to monitor their temperatures, I saw that they would sometimes all cut out at the same time, and display "N/A" in place of a temperature.

Screenshots of TG Pro results:

http://imgur.com/OR1IN22

http://imgur.com/YrOhCEY

So, I went ahead and cleaned out and reapplied new Arctic Silver 5 thermal paste on the heatsink, hoping that the problem was due to a bad connection. This did not work however, and there has been no change in spike temperatures.

Are my Northbridge sensors broken? It seems strange that they would be reading such high temperatures all of a sudden for no apparent reason, when the CPU is not overloaded and there have been no significant hardware changes. If this is the case, what is the necessary solution?

Thanks!

Answered! View the answer I have this problem too

Is this a good question?

Score 1

Comments:

Can you please properly identify your MacBook model and year using the ultimate Mac lookup on everymac?

The format should look similar to this:

MacBook Pro i5 (2.7) 15" 2010 8G.

I'm thinking it's either caused by liquid damage or thermal paste gone dry. Because I think the north bridge is under the heatsink plate but I could be wrong.

by

@benjamen50 Sure! It's a mid-2010 MacBook "Core 2 Duo" 2.4 13"

by

Add a comment
Black Friday
Broken doesn't stand a chance.

2 Answers

Chosen Solution

My first guess would come from your statement that you lubed the fan. That probably killed it. Remove the screws from the bottom and take the bottom off. Boot the machine and take a look to see if it is running.

MacBook Unibody Model A1342 Fan Replacement

Next, when you did the thermal paste replacement did you see any evidence of an oily residence on the logic board around the heat sink?

Was this answer helpful?

Score 2

Comments:

Earlier in the process, I removed the fan and lubricated the axle before replacing it, and this did not kill the fan. The fan is not the problem, it has been functioning properly but running at 6200rpm, its maximum speed (It makes so much noise at 6200rpm that taking the back off to look if it's spinning isn't necessary). It's running because of the high readings of the Northbridge sensors.

Second part of your answer: when I removed the heatsink to replace the thermal paste, there was built-up paste residue on the heatsink and processor surfaces, but nowhere else on the logic board. It wasn't anything in excess of what one would expect to find, and confined to where it should be.

by

What I have run into several times is the liquid filled heat sink leaking. It's very hard to diagnose but the residue is a give away. Take a look for it.

by

Add a comment

Try to re-apply thermal paste and make sure it is making good contact.

Was this answer helpful?

Score 1

Comments:

I was reading about possibly having to do this! Would these guides be sufficient for showing how to do it?

MacBook Unibody Model A1342 Logic Board Replacement

How to Apply Thermal Paste

by

@gigabit87898 Definintly! On the first guide, only go up to 22. Then use the second one and clean the old paste off.

by

I think the sensors themselves are fine because they aren't reporting a crazy number like -120, 3000°F.

by

I went through those guides and replaced the thermal paste with Arctic Silver 5, but to no avail. My Northbridge temperatures are still sky high!

http://imgur.com/a/516Wp

What else could I do?

by

Honestly, i dont have a clue. maybe @oldturkey03 or @mayer has a suggestion?

by

Add a comment

Add your answer

matthew.karkut will be eternally grateful.
View Statistics:

Past 24 Hours: 1

Past 7 Days: 4

Past 30 Days: 20

All Time: 200