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halfpiint

macrumors newbie
Original poster
Dec 16, 2021
10
1
All of a sudden I heard a loud sound yesterday so I immediately turned off my iMac. Since it's been feeling very hot lately I'm assuming it's the fan that's going bad. Otherwise it runs great and I can't afford to replace it so I need to ask
How much will it cost to replace the fan? and
Can I do it myself? I upgraded the memory myself but that was very easy to access.
Looking forward to your response. Thanks a bunch!

27" late 2009 iMac
MacOS High Sierra v. 10.13.6
Processor: 2.8 Ghz Intel Core i7
Memory: 16gb
 
Try running the apple hardware diagnostic test. It gives a lot of false negatives, but the problems found are usually accurate.

If I recall correctly, you have multiple fans in your model, and if there is a problem with it, the Apple hardware diagnostic test might be able to narrow down what fan is having issues.

I got a diagnostic code for the HDD fan before on a similar model, I didn't have to replace it, I just cleaned it. The code went away.

The fans them selves are not expensive, and depending on your level of skill, replacing the fan may not be that difficult.

Are you using the original HDD? I'm surprised that it last as long as it did. While you have your iMac open to replace/clean the fan, I would replace the HDD with a SATA SDD.

I have no idea how much someone was charged to do this for you.
 
All of a sudden I heard a loud sound yesterday so I immediately turned off my iMac. Since it's been feeling very hot lately I'm assuming it's the fan that's going bad. Otherwise it runs great and I can't afford to replace it so I need to ask
How much will it cost to replace the fan? and
Can I do it myself? I upgraded the memory myself but that was very easy to access.
Looking forward to your response. Thanks a bunch!

27" late 2009 iMac
MacOS High Sierra v. 10.13.6
Processor: 2.8 Ghz Intel Core i7
Memory: 16gb
 
Fixit offers 3 different fans. How do I tell if it's the Hard Drive Fan or the Optical Fan or the CPU fan?
I cannot remember which app it is but there are apps that monitor temp of specific parts. I am unsure but I think iStat can do this.

If it indicates either of those 3 parts are too hot then odds are that's the fan that got busted.

I noticed that your computer is from the year 2009.

This is over 13 years old.

This break down may serve as an incentive for you to get a newer iMac like the 2020 iMac 27" Core i5 or a 2021 iMac 24" M1.

Power consumption and thermal heat output would be much lower than your 2009.
 
Macs Fan Control reports fan speed and allows the user to manually control fans.

https://crystalidea.com/macs-fan-control/support

This may help to determine if the fan is working.

*Edit: I just checked on a few systems here and Mac Fan Controls (free version) only has a 'fan speed' report but doesn't specify which fan.

However it does reports temps for different sensors,
 
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Try running the apple hardware diagnostic test. It gives a lot of false negatives, but the problems found are usually accurate.

If I recall correctly, you have multiple fans in your model, and if there is a problem with it, the Apple hardware diagnostic test might be able to narrow down what fan is having issues.

I got a diagnostic code for the HDD fan before on a similar model, I didn't have to replace it, I just cleaned it. The code went away.

The fans them selves are not expensive, and depending on your level of skill, replacing the fan may not be that difficult.

Are you using the original HDD? I'm surprised that it last as long as it did. While you have your iMac open to replace/clean the fan, I would replace the HDD with a SATA SDD.

I have no idea how much someone was charged to do this for you.
Where do I find the apple hardware diagnostic test? Don't worry, I'll google it!

My Skill level in the hardware dept is low but I can follow directions easily. I doubled my RAM years ago and my iMac has been flying ever since. I use it everyday. It runs better and faster than my 2015 Macbook Pro. That's why I'd love to save it. It isn't often you get a computer that hangs in there for you and I can't afford to replace it, but thanks for your feedback. it's greatly appreciated.
 
I cannot remember which app it is but there are apps that monitor temp of specific parts. I am unsure but I think iStat can do this.

If it indicates either of those 3 parts are too hot then odds are that's the fan that got busted.

I noticed that your computer is from the year 2009.

This is over 13 years old.

This break down may serve as an incentive for you to get a newer iMac like the 2020 iMac 27" Core i5 or a 2021 iMac 24" M1.

Power consumption and thermal heat output would be much lower than your 2009.
Gosh, I don't need an incentive to upgrade. I just Wish I had the funds for a newer iMac but I don't and I don't see anything promising on the horizon, so I'm hopeful I can save my iMac, but thanks anyway
 
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I have 2 questions: #1 about the Apple Hardware diagnostic test and the other about the Fan control

I'm getting 2 different instructions on running the diagnostic and thought I'd check with you as to which instructions to follow . I'll check back in the morning for a response before giving it a go.
  • 1 Press F10 at startup.
  • In the left pane of Lifecycle Controller, click Hardware Diagnostics.
  • In the right pane, click Run Hardware Diagnostics.

  • 2nd INSTRUCTIONS
  • #2 Turn on Mac, immediately press & hold the D key on your keyboard as your Mac starts up.
  • Release when you see a progress bar or you're asked to choose a language
FAN CONTROL:

I've just download the Fan control and saw this message

"This program is for advanced users who know how to use it without doing harm to their macs. The authors are not liable for data loss, damages, profit loss or any other types of losses connected with the use or misuse of the program."

Is there something I need to know, like in something not to touch? haha
Again, thank you so much for your feedback.
 
Here's the Mac Fan Control screenshot of all the temperatures.
 

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Kind of surprised at the number of people saying you should turn on a computer that may catch fire, just to run diagnostics. You say you heard a loud noise so it could also be the power supply. Make sure you leave the iMac shut down and unplugged.

This iMac has a front glass that is held on with magnets, and the removal of the LCD is pretty easy if you follow the directions on iFixit (or OWC, or any decent YouTube video).

Once you have the LCD out, the fans are right there in front of you, as is the power supply. Considering you heard a loud noise, take a look at everything and see if any appear scorched or burnt. Take precautions when working around the power supply as it's a possible electrocution hazard, but if you're sensible and don't start getting handsy with it, it's not much of a problem.

Edit: Buying a replacement fan should be relatively cheap on eBay or other sources. The power supply would be a little more but nothing to break the bank.
 
Thank you for taking the time to leave your detailed response. Can I bother you for a link to the directions?

How will I know which fan needs replacing? or whether it's the power supply? I assume I should UNPLUG the iMac first

btw, was there anything you saw alarming in the Fan Control screenshot above ?
I'm a senior citizen and can follow instructions so long as I have faith in my advisors.
 
Until you get the problem resolved it would be safest to keep the iMac unplugged even when not working on it. But yes, you do want to have it unplugged when you open it up.

iFixit has a teardown, which gives you an overview of what's inside, and there is an Apple Service Manual for the 2009 iMac that gives the take-apart for how to replace the fans (along with a whole bunch of other information). Watch the teardown and read the manual (both several times) to get familiar with the insides.

I would think that if one of the fans died it would show 0 (zero) RPM in MFC. Your power supply does look a bit toasty compared to my 2020 iMac but that may just be because you have a hard drive and I have an SSD.

The only way you'll know if something needs replacing is to open it up and see. Most things that make loud noises when they break also tend to leave behind evidence of their self-destruction. Once you have it open, take a look at the fans and power supply and see if you see anything obvious, like soot or burn marks. Considering how old your iMac is, you could have the fans clogged with dust and eventually one of them couldn't take the strain and let out the "magic smoke". While you have it open you should clean it out with some canned compressed air. And replacing the coin battery would be good too since they're only rated for about seven years.
 
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Coin battery? and do I really need the $15+ shipping heavy duty suction cups? At the risk of sounding like a wimp, this is getting scary!

 
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Anyone know What year did iMac come with the SSD Drive?
It isn't important as your 2009 iMac can easily accept any 2.5" SSD. You just need to order the 3.5" drive to 2.5" drive bracket adapter so you can securely attach your new SSD.
 
Coin battery? and do I really need the $15+ shipping heavy duty suction cups? At the risk of sounding like a wimp, this is getting scary!

On the logic board there is a coin shaped battery (BR2032, not easy to find, but you can substitute the cheaper CR2032 which is available everywhere). The battery keeps the internal clock ticking when you turn off the iMac, and also powers a small bit of RAM that stores some of the system settings.

You don't really need the suction cups but they do makes things easier. The 2010+ iMacs have the glass right up to the edge of the case, which means you could use a fingernail to pry it up (but be very careful not to break the glass). The 2009 unfortunately has a metal bezel that makes it harder, since the glass is inset in the front face. You don't need expensive heavy-duty suction cups. Even the cheap ones people stick on refrigerators or window glass would work. But you do need to be very careful of the glass coming loose and then falling and breaking.

I'm not sure about when the iMacs started having SSDs but I do know that there was a kit to put one into a 2010. You could replace your internal HD with one (doesn't have to be Apple brand). You can't use the newer NVMe SSDs but there are the 2.5 inch ones with the same SATA connectors that the HDs use. Crucial, Samsung, and others still sell these. Be aware that you'd also need to get a bracket to adapt the 2.5 inch form factor to the 3.5 inch size where the HD sits.
 
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On the logic board there is a coin shaped battery (BR2032, not easy to find, but you can substitute the cheaper CR2032 which is available everywhere). The battery keeps the internal clock ticking when you turn off the iMac, and also powers a small bit of RAM that stores some of the system settings.

You don't really need the suction cups but they do makes things easier. The 2010+ iMacs have the glass right up to the edge of the case, which means you could use a fingernail to pry it up (but be very careful not to break the glass). The 2009 unfortunately has a metal bezel that makes it harder, since the glass is inset in the front face. You don't need expensive heavy-duty suction cups. Even the cheap ones people stick on refrigerators or window glass would work. But you do need to be very careful of the glass coming loose and then falling and breaking.

I'm not sure about when the iMacs started having SSDs but I do know that there was a kit to put one into a 2010. You could replace your internal HD with one (doesn't have to be Apple brand). You can't use the newer NVMe SSDs but there are the 2.5 inch ones with the same SATA connectors that the HDs use. Crucial, Samsung, and others still sell these. Be aware that you'd also need to get a bracket to adapt the 2.5 inch form factor to the 3.5 inch size where the HD sits.
I'd opt for the Crucial branded ones as they are cheaper but still reliable.

It may be slower by <50MB/s than any Samsung but you'd not notice it from day to day operations.
 
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Here's the Mac Fan Control screenshot of all the temperatures.

I don't see any issues from the readings of temperatures and fan speed in this picture.
Maybe the loud noise you heard came from
- The speakers rather than the blown-up capacitors inside your iMac. If your iMac are still operational, play some music and listen to the speaker if there is any issues in the sound output.
- The broken hinge of the tilting mechanism. Use your hand to adjust the screen to see itf it still works.
- A crack in the fan plastic frame. The fan is detached from the case but it still spins. I have 2 broken fans with this status, I fixed it with some strong glue.

And as advised by @rpmurray, keep your iMac away from other flammable items in your house. Take it outside or to the garage to do the checking.

If the PSU has any blown capacitors, you will have to un-screw it from the chassis, flip it over to have a look. This process itself is already 45% from a complete disassembling of your iMac.

Anyway, it all depends on the level of your skill set in working with the iMacs. If you haven't got the idea on how to work inside the iMac, view at least a dozen times some Youtube videos (I did learn this way) before actually lay your hands on it.

For your iMac 27" 2009:
- You can use your finger nails to open the protection glass (I do use my fingernails all the time). Just don't apply sudden and strong force while doing it. If using suction cups, remember to use 2 small ones on both top conner, not a big one in the middle. The big one will loose balance and crack your glass.
- When replacing the HDD with SSD, you can just let the SSD dangling there or tape it to the aluminum case. I simply bolt it to the stock metal HDD frame with 1 screw. Don't need to use the 3.5" to 2.5" adapter unless you plan to use 2 SSD in the same place of the old HDD.
 
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I'd opt for the Crucial branded ones as they are cheaper but still reliable.

It may be slower by <50MB/s than any Samsung but you'd not notice it from day to day operations.
Yeah, I just added the Samsung so the OP could see that there are a variety to choose from, and not just the ones I mentioned. Even with the Crucial being a tad slower it's still leaps and bounds above the the speed of any HD.

The OP may want to see if there are any computer repair places nearby if they don't want to try it themselves. I've opened a ton of these so they don't scare me anymore, but when I first did one I was so nervous that I would break something. Or they may have a tech inclined friend who would do it for free. I've done upgrades for friends, both hardware and software, for free except the cost of any components that need to be replaced. The manual I linked to gives some pretty detailed instructions on how to take the iMac apart, fix whatever needs fixing, and put it back together. I do recommend watching several different YouTube videos on the process, just because some may leave out a step that looks obvious but isn't to someone whose never done it before.
 
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