That is page #28, which shows the LED location.
Page 29 and 30 has a list of the LED functions, and then lists the LED sequence during startup.
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HDD died, Internet recovery not working.... HELP!
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Page 29 and 30 has a list of the LED functions, and then lists the LED sequence during startup.
Thanks, I know this is going to be silly but How am I supposed to see those LEDs when the display screen is on the computer?
Can I start the computer with the glass off and holding the screen forward to see behind? in a safe fashion?
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I think that you can see the LEDs from the bottom RAM opening. Remove the little cover where you change the RAM.
Put the iMac down on its back.
Plug the power cord while looking up inside past the right end of the RAM slots.
Watch for an LED to light up when you plug in the power cord. If you don't see it light up, unplug, wait 10 seconds, then plug the power cord in again. Be sure to watch for the LED to light up. It will be about 5 inches (maybe 12 cm?) from the bottom.
If you can see that one LED, then press and release the power button. You should see #2 light up. And you would be waiting for a #3 LED, which should come on. If the #3 does not light up, then likely a problem with the graphics card.
I don't think that all the optional graphics cards are the same size, i'm not completely sure about that. But your "new" card doesn't do as much as the old card ?? If you can discover those troubleshooting LEDs, and the "new" card doesn't get to the #3 LED on boot, then put your old card back in place, and try that one for the LEDs. Does it go any further, to #3, then you get the #4?
I had a 2011 21-inch iMac a couple of weeks ago with a similar problem - reseating the graphics card fixed the boot issue on that one.
finally, if you can't see ANY leds come on from the bottom, you SHOULD see one or two at least, but if you see nothing, then the only recourse is to remove the front glass, and unscrew the display panel. you can pull the top edge of the screen forward a couple of inches (Be REALLY careful here. You can do this without disconnecting any cables, but it is really easy to jerk the display and snap a connector loose. Watch for the cables, you only want enough space to look down from the top. You should see the LEDs from above, this is what I had to do on the smaller iMac that I was working on.
Put the iMac down on its back.
Plug the power cord while looking up inside past the right end of the RAM slots.
Watch for an LED to light up when you plug in the power cord. If you don't see it light up, unplug, wait 10 seconds, then plug the power cord in again. Be sure to watch for the LED to light up. It will be about 5 inches (maybe 12 cm?) from the bottom.
If you can see that one LED, then press and release the power button. You should see #2 light up. And you would be waiting for a #3 LED, which should come on. If the #3 does not light up, then likely a problem with the graphics card.
I don't think that all the optional graphics cards are the same size, i'm not completely sure about that. But your "new" card doesn't do as much as the old card ?? If you can discover those troubleshooting LEDs, and the "new" card doesn't get to the #3 LED on boot, then put your old card back in place, and try that one for the LEDs. Does it go any further, to #3, then you get the #4?
I had a 2011 21-inch iMac a couple of weeks ago with a similar problem - reseating the graphics card fixed the boot issue on that one.
finally, if you can't see ANY leds come on from the bottom, you SHOULD see one or two at least, but if you see nothing, then the only recourse is to remove the front glass, and unscrew the display panel. you can pull the top edge of the screen forward a couple of inches (Be REALLY careful here. You can do this without disconnecting any cables, but it is really easy to jerk the display and snap a connector loose. Watch for the cables, you only want enough space to look down from the top. You should see the LEDs from above, this is what I had to do on the smaller iMac that I was working on.
ok, thanks for the great info. I'll try this later tonight. I sure hope I don't need to get tot hat card again... lots of wire and stress...lol
Sorry for the delay, hurt my back and that thing is so heavy to move around...lol
Couldn't see anything in the RAM SLOT area but was able to see thru the mesh bottom grill.
YES - when plugging the power cord, the 1st LED light came on inside and stayed on.
YES - when i pushed the power button, the 2nd LED light came on inside and stayed on.
NO - Waited 10 minutes to make sure because didn't know if it was instant or took time... 3rd and 4th light NEVER came on.
As for taking everything apart again. Can we assume at this point that this new GPU card is defective? Because when I had my old card, the screen would come on. I would be able to see the apple logo, progress bar and a grey background. Now all I see is PURE BLACK?
The #3 LED should light when the screens lights up. Your screen does not light up with the "new" card, for whatever reason.
Could be the "new" graphics card.
It's a royal pain to swap the card, but you will need to swap out the new card with old, to see if the full sequence of LEDs is showing with the old card, then verify again with the new card (which you might not have completely seated the first time). Verify ALL the logic board connections as you open it back up...
I'm thinking that you might have bought a graphics card that is not directly supported on a Mac. Looks similar, but not actually supported by the Mac OS.
Or, you were "lucky" enough to get one of the cards that are sold as "parts-only", and not a tested card. There's often a reason for a low-end price.
Could be the "new" graphics card.
It's a royal pain to swap the card, but you will need to swap out the new card with old, to see if the full sequence of LEDs is showing with the old card, then verify again with the new card (which you might not have completely seated the first time). Verify ALL the logic board connections as you open it back up...
I'm thinking that you might have bought a graphics card that is not directly supported on a Mac. Looks similar, but not actually supported by the Mac OS.
Or, you were "lucky" enough to get one of the cards that are sold as "parts-only", and not a tested card. There's often a reason for a low-end price.
Not a pro here, but how can a card not "have completely seated the first time" ? Because I put it in there all the way and also when you screw everything together all the screw holes were aligned perfectly so doesn't that mean it was in place properly because I would think if it was not it wouldn't fit. Just trying to learn, not doubting your information. Thanks!
The new card is not working. A reseat is one of the troubleshooting steps that you can try.
The old card was working (at least to light up the screen and show visual elements/icons/etc.), so first step for me would be swapping the old card back in place.
If you get video, swap back to the new card to verify that it is, indeed, bad (screen still does not light up).
It's a chore to get in and out of those iMacs, but if you do want it to work again, this is what you get to do...
I suspect the new card is either no good, or is simply incompatible with your Mac (maybe not originally a Mac card. Not every graphics card that "fits the connector" is compatible with Mac hardware, if it was not originally made compatible for a Mac. The reason also doesn't matter too much, when the card simply does not work. Verify that with a swapout. If you still get no video the second time, send it back, get a different card, ask if the card has been tested, etc, etc.
The old card was working (at least to light up the screen and show visual elements/icons/etc.), so first step for me would be swapping the old card back in place.
If you get video, swap back to the new card to verify that it is, indeed, bad (screen still does not light up).
It's a chore to get in and out of those iMacs, but if you do want it to work again, this is what you get to do...
I suspect the new card is either no good, or is simply incompatible with your Mac (maybe not originally a Mac card. Not every graphics card that "fits the connector" is compatible with Mac hardware, if it was not originally made compatible for a Mac. The reason also doesn't matter too much, when the card simply does not work. Verify that with a swapout. If you still get no video the second time, send it back, get a different card, ask if the card has been tested, etc, etc.
GOT IT. I greatly appreciate your time. I am learning so much. I also now know for sure that when I went in the GRAPHIC WORK lane years ago I did the right thing.... design is more my happy place than the fixing part! lolThe new card is not working. A reseat is one of the troubleshooting steps that you can try.
The old card was working (at least to light up the screen and show visual elements/icons/etc.), so first step for me would be swapping the old card back in place.
If you get video, swap back to the new card to verify that it is, indeed, bad (screen still does not light up).
It's a chore to get in and out of those iMacs, but if you do want it to work again, this is what you get to do...
I suspect the new card is either no good, or is simply incompatible with your Mac (maybe not originally a Mac card. Not every graphics card that "fits the connector" is compatible with Mac hardware, if it was not originally made compatible for a Mac. The reason also doesn't matter too much, when the card simply does not work. Verify that with a swapout. If you still get no video the second time, send it back, get a different card, ask if the card has been tested, etc, etc.
Ok, surgery time again... lets hope the patient survives!
OK, surgery done. I feel like a pro I did that so fast...lol
I took the "REPLACEMENT CARD" out
Put the OLD CARDS back in... computer started, screen is on
and ALL 4 LIGHTS are on. I feel good that at least it looks like I am doing this stuff correctly.
So does that mean the "REPLACEMENT CARD" is bad? Even if the guy checked the serial number to say it works on my computer?
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hmmm...
More fun, eh? You are having what I call a grand holiday!
Now that you know what the LEDs are supposed to show in a working system, you could try the "new" graphics card one more time. So, if you are convinced it is not going to work - Your replacement graphics card is either bad, or is not compatible with a Mac. The various cards that use that connector look very much alike, but specific models may need different hardware (or won't work in a Mac at all), and might work in a compatible Windows PC.
Then, you might try getting your money back - explain that you were expecting a card that works, not one that doesn't work in your iMac. Good luck on that...
More fun, eh? You are having what I call a grand holiday!
Now that you know what the LEDs are supposed to show in a working system, you could try the "new" graphics card one more time. So, if you are convinced it is not going to work - Your replacement graphics card is either bad, or is not compatible with a Mac. The various cards that use that connector look very much alike, but specific models may need different hardware (or won't work in a Mac at all), and might work in a compatible Windows PC.
Then, you might try getting your money back - explain that you were expecting a card that works, not one that doesn't work in your iMac. Good luck on that...
Thanks so much for all the help/info. I don't think I will have problem getting a refund. I guess I need to see what I am going to do next.