Hi all my Macbook Pro Early 2008 randomly shuts off and leaves this in the console, 2018-03-21 2:11:35.000 PM kernel[0]: Previous shutdown cause: -81

I cannot find any information about -81.

I have reseated the RAM, Replaced thermal Paste and tried removing the battery and running from AC to no avail.

Any suggestions are appreciated.

Update: Apple hardware test, says it's a RAM issue, although running Rember gives no issue. Image of Apple Hardware test:

enter image description here

  • I would say motherboard or power circuit.
    – SEJU
    Mar 21, 2018 at 21:45

1 Answer 1


Negative shutdown codes are hardware related. If Apple Hardware Test is telling you that there was an issue with memory, you can be quite certain that the test is accurate.

Re-seating the RAM is not a sufficient test. You need to remove the memory modules and test each one independently in each of the slots. If you have two modules and two slots, you will perform four tests in total. Make a note of what fails where.

What you are testing for is either a bad memory slot or a bad module. If your memory slot is bad, you'll need to replace the logic board. If the memory is bad, you will need to get a new module.

How will you know?

If all memory fails in one slot and not another, it's that slot. If one module fails in both slots, it's that memory module.

  • It would seem that one of my RAM Sticks was faulty, ordered 2 new 2gb sticks and has solved the issue. Mar 23, 2018 at 4:52

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .