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-   -   3 beeps on Startup, but runs perfect on Target Mode? (http://www.mac-forums.com/forums/apple-notebooks/302947-3-beeps-startup-but-runs-perfect-target-mode.html)

MDJCM 09-05-2013 06:52 AM

3 beeps on Startup, but runs perfect on Target Mode?
 
Trying to work this one out.

MBP ~2011 13", has had a spill on keyboard BUT, will boot perfectly from another Mac's firewire'd target mode hard drive. The only broken hardware appears to be a usb port and the trackpad. It otherwise functions fine. :Cool:

If I try to boot it from its own drive or a Snow Leopard DVD, it gives the 3 beeps.

So I've replaced the hard drive, and went to install from the DVD but still giving the 3 beeps.


I mean, if it works fine over Target Mode, doesn't that prove that everything is fine except the HDD? :Confused::|


(I am aware 3 beeps is a RAM issue, have tried every configuration of RAM/slot and the pattern is the same, no boot from own drive or DVD but ok boot over firewire)

bobtomay 09-05-2013 07:32 AM

If it works in Target Disk Mode and you can see the hard drive and copy from it to the host computer, it is not a hard drive issue.
That's what it is for, to allow you to get data from an otherwise non-functioning machine.
As the beeps indicate, it is a RAM issue.

My best guess based on the spill, would be the slots or the path from the slots have been affected rather than the RAM modules themselves.

You can test that by trying the modules in another computer to verify they are working or not.

MDJCM 09-05-2013 07:36 AM

Quote:

Originally Posted by bobtomay (Post 1535213)
If it works in Target Disk Mode and you can see the hard drive and copy from it to the host computer, it is not a hard drive issue. As the beeps indicate, it is a RAM issue. My best guess based on the spill, would be the slots or the path from the slots have been affected rather than the RAM modules.

When I tested the MBP in Target Disk Mode, I actually meant the reverse of that, in order to test if the the MBP was in good shape I had it Host another Mac's HDD with no problems at all. The Mac mini's HDD booted fine over Target Mode on the MBP hardware.

The part I don't understand is, if it was a true RAM or Logic Board issue, why would it be faultless at hosting another Mac's HDD over firewire?

bobtomay 09-05-2013 08:53 AM

Now that is a good question...

???

You could boot it repeatedly in that way - e.g. not a one time fluke?

Perhaps a response from one of our members that do hardware repair on a regular basis may have more insight.

pigoo3 09-05-2013 09:26 AM

Quote:

Originally Posted by MDJCM (Post 1535208)
MBP ~2011 13", has had a spill on keyboard BUT, will boot perfectly from another Mac's firewire'd target mode hard drive. The only broken hardware appears to be a usb port and the trackpad. It otherwise functions fine. :Cool:

If I try to boot it from its own drive or a Snow Leopard DVD, it gives the 3 beeps.

I mean, if it works fine over Target Mode, doesn't that prove that everything is fine except the HDD? :Confused::|

Liquid spills can be VERY VERY unpredictable. Accessing a computer via Target Disk mode...and booting the computer from it's own HD or optical drive are different. Accessing a computer via Target Disk mode is sort of treating that computer as an external hard drive (which is VERY different from booting a computer from it's own HD). Apparently this difference was effected by the liquid spill.

I agree with bobtomay...the problem is probably not a hard drive issue.

Something electronic on the logic board was most likely damaged with the liquid spill...and this "electronic thing" must be a requirement in the startup/booting process. There are 1000's and 1000's of circuits on a logic board...and this is something that cannot be repaired by a user. This is why liquid spills almost always result in the need for a replacement logic board ($$$).

- Nick

pigoo3 09-05-2013 09:31 AM

Looking at this situation logically...this computer experienced a liquid spill. If liquid wasn't spilled on it...the computer would still be working fine. After the liquid spill it is not working fine. Thus the liquid spill caused damage.

Yes the liquid was spilled on the keyboard. But directly under the keyboard is the logic board. And powered on logic boards are VERY easily damaged by liquids.

Sorry to hear about this. But if I was a betting person...I would bet that the logic board was damaged...and a replacement logic board is needed.

- Nick

MDJCM 09-05-2013 09:56 AM

Cool, just set up a 10.8 install on a USB drive, and it boots to that install just fine, tested Target mode again, boots just fine. Tested reverse-firewire boot mode, also boots fine.

Tried to boot to Snow Leopard DVD = 3 beeps

So I took the SATA drive out of the external USB 10.8 drive and put that in the MacBook and its booting up fine now out of it's own HDD.

Will continue testing. I know liquid spills can have random effects on computers, fair enough. I hope somehow now it holds steady for a while. It's just weird that it would have very selective start up troubles, depending on source.

pigoo3 09-05-2013 10:25 AM

Quote:

Originally Posted by MDJCM (Post 1535227)
So I took the SATA drive out of the external USB 10.8 drive and put that in the MacBook and its booting up fine now out of it's own HDD.

Well...maybe this is the rare situation where the hard drive did get damaged by the liquid spill. In many many cases the HD survives a liquid spill.

If the MBP is booting fine from an external HD that was transplanted into it...hey that sounds great!

- After installing this HD (that was formerly an external HD)...are you still getting the 3 beeps?
- Are you able to boot from the Snow Leopard DVD (no beeps)?

Congrats so far,:)

- Nick

MDJCM 09-05-2013 11:12 AM

Quote:

Originally Posted by pigoo3 (Post 1535229)
Well...maybe this is the rare situation where the hard drive did get damaged by the liquid spill. In many many cases the HD survives a liquid spill.

If the MBP is booting fine from an external HD that was transplanted into it...hey that sounds great!

- After installing this HD (that was formerly an external HD)...are you still getting the 3 beeps?
- Are you able to boot from the Snow Leopard DVD (no beeps)?

Congrats so far,:)

- Nick

Just to confuse things further, the drive i took out of the usb caddy was the original drive in the MBP, I took it out for testing and thats the one that's gone back in now.

So it wasn't even a HDD fault :Confused::\

straaaange

pigoo3 09-05-2013 02:27 PM

Quote:

Originally Posted by MDJCM (Post 1535240)
So it wasn't even a HDD fault :Confused::\

Are you now saying everything is fine? Boots from the internal HD?...and no beeps?

- Nick

Stretch 09-05-2013 04:03 PM

Might be an issue with the SATA port on the logic board or SATA ribbon cable in the MBP if I'm reading correctly.

MDJCM 09-08-2013 09:31 AM

Quote:

Originally Posted by pigoo3 (Post 1535276)
Are you now saying everything is fine? Boots from the internal HD?...and no beeps?

- Nick

Yep, so I took out the original HDD and put it in a USB caddy, formatted and installed 10.8 over USB (via a different Mac), and put the drive back in the MBP and now it boots fine without 3 beeps.

I'll check if it now accepts booting off the Snow Leopard DVD, as that was consistently giving the 3 beeps before.

MDJCM 09-14-2013 08:29 AM

Oh yeah, still hates booting to Snow Leopard DVD, but boots fine to Mac OS in internal drive.

LexS 09-15-2013 03:39 PM

3 beeps
 
3 beeps on startup means RAM problem: wrong RAM, Ram failure, or reseating necessary.
No software problem, no main board problem, no disk problem (that's why it still works in Target Disk mode)

MDJCM 09-15-2013 06:29 PM

Quote:

Originally Posted by LexS (Post 1537103)
3 beeps on startup means RAM problem: wrong RAM, Ram failure, or reseating necessary.
No software problem, no main board problem, no disk problem (that's why it still works in Target Disk mode)

Except, it's booting from its own internal drive now repeatedly without errors or beeps

Only beeps on DVD boot


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