MacBook Pro Dies (Rabbit Hole)

The company that replaced the SMC suggested thermal paste on the heat sinks. You think that will help?

Yes! Thermal paste dries out and gets crumbly and the SMC will unceremoniously shut down the Mac when the CPU overheats. Old paste should be scraped off and replaced with new paste as a matter of course whenever the Mac is apart. That would be a really easy fix.

The CPU was definitely getting too hot (cycles around 140 F...

FWIW, 140F (60C) while a bit warm is really not bad for a CPU temp these days, especially in

a laptop. Intel "I" series CPUs are spec'd at a max 100C (212F).

However, if any other components are getting that hot, especially power supply, that

can be a real issue. Actually, sometimes all it can take is a single weak solder joint

at a critical spot, and may not even be intuitive obvious location. Can also be something

that is shorting out that when cold is okay but expanding with heat makes contact with

something it shouldn't. Cranking the fan up is likely just a bandaid solution as these

types of problems almost always get worse.

But as John stated and my own experience working in the electronic design arena most of my life,

tracking down an thermal issue, especially something as complex as a computer can be quite

challenging.

Hi, crashinc99 !

A serious question for you : what is preventing you from taking the MacBook Pro to an AASP for a proper set of diagnostics? It seems better to make decisions based on certainties as opposed to speculation.

You stated you have iStatMenu (which I use) just pull up a drop

down of the temps, do a screen shot then post here.

Mine for my iMac is like this:

AASP quality is inconsistent at best. An Apple Store would either fix the problem with a guarantee, or they would charge a nominal diagnostic fee.

I agree with their diagnosis though... replace the whole logic board. If they can't do it, or Apple won't do it, then go to PowerBook Medic. They'll also guaranteed their work (90 days as I recall).

TSQF implies a thermal sensor but it's anyone's guess which one of a Mac's many thermal sensors it could be. The fact Apple Diagnostics cannot finish hinders further investigation.

Instead of running the fan at that high a level all the time, decreasing

its life, you can setup fan speed "temperature zones by setting

Automatic Fan Rules.

The speeds aren't shown, but this shows the temp ranges I set up

on my iMac each with a custom speed:

• Before I had the SMC chip replaced, Apple Diagnostics ran fine and it reported no battery.

That's where your troubles began and it appears that's where they remain. No battery means essentially nothing will work on a portable Mac.

I think you went off in the wrong direction by replacing just the SMC chip. Obviously it didn't solve the problem. The next likely candidate would be the entire logic board which is best replaced as a unit. The dc-in board can be inexpensively replaced but I doubt it's the problem. It sounds as though thermal cycling is causing an intermittent power failure, somewhere on the logic board. Finding the exact broken component or connection is next to impossible.

Component level repair has become a lost art, but if you want to explore your options consider Powerbookmedic. Give them the whole MacBook Pro, battery and all (more about that later) not just the logic board. If you had unauthorized work performed on your MacBook Pro Apple will henceforth refuse to service it, but Powerbook Medic can probably help. They are reputable and the prices they charge are unreasonably cheap. Do it before they change their mind. Be prepared to wait a while though. Months, conceivably. They get a lot of Macs.

• Thinking it might be RAM (given the Apple Diagnostics issue), I installed a RAM chip known to be working. Same effect when running diagnostics, blackout.

That was a good idea; of course RAM diagnostics require everything else associated with memory to work. The spontaneous shutdown supports a suspicion of some other logic board defect. So does the audio port problem.

• I am using an Apple brand battery.

Apple does not make their batteries available to anyone other than authorized Apple repair facilities. Unless you used the services of one of them, there is no way to determine whether that battery is suitable or not.

A genuine "Apple brand battery" can only be obtained by an AASP or an Apple Store, or it was used and pulled from a used Mac. Of course there are plenty of places that sell "Apple OEM" batteries. If they really are genuine then they should have been disposed of, because they either did not meet Apple's quality assurance tests, or they were exposed to excessive environmental conditions such as a fire or flood or were dropped or crushed or any number of other reasons Apple might have rejected them. Or, they're simply counterfeit which is distressingly common.

Defective batteries can be very hazardous. That's the reason only Apple or an AASP should replace them. The only reason to use anything else would be if a Mac is "vintage" or otherwise unsupported and no other choice exists. In that case the liability is yours, so choose a reputable vendor of aftermarket batteries. They will not bear the Apple brand. Powerbook Medic can rule out your battery as the problem, or supply a suitable aftermarket alternative if it is.