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TS1541: Solutions for troubleshooting installation, startup, and login issues in Mac OS X v10.5

Learn about Solutions for troubleshooting installation, startup, and login issues in Mac OS X v10.5

TS1541 Mac Pro won't start up, flashing light is as far as I can go.

1142 Views 1 Reply Latest reply: Feb 23, 2013 4:49 PM by BDAqua RSS
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Feb 23, 2013 3:04 PM

I'm having an issue of starting the Mac Pro. I've taken the memory modules out, to reset them, but the manual doesn't give a lot of options for this issue. Anyone know why this happens, or even better yet, know how to resolve this issue?


Mac Pro, Mac OS X (10.5.1)
  • BDAqua Level 10 Level 10 (114,685 points)

    Any tones, or repeating sequence of flashes?


    The following table lists the new tones and their meaning:


    Tone(s)    Description

    1 tone, a 5-second pause, repeat    No RAM installed

    3 successive tones, a 5-second pause, 3 successive tones    RAM does not pass data integrity check

    1 long tone when holding down the power button    Firmware upgrade in process. See About firmware updates for Intel-based Macs for more details.

    3 long tones, 3 short tones, 3 long tones    Firmware restoration from CD in process. See About the Firmware Restoration CD (Intel-based Macs) for more details.



    Older meanings...


    Can you count the beeps or flashes?


    1 beep = no RAM installed

    2 beeps = incompatible RAM types

    3 beeps = no good banks

    4 beeps = no good boot images in the boot ROM (and/or bad sys config block)

    5 beeps = processor is not usable


    In addition to the beeps, on some computers the power LED will flash a corresponding number of times plus one. The LED will repeat the sequence after approximately a 5-second pause. The tones are only played once.


    Note: In this case, a flash is considered to be 1/4 second or 250 ms or greater in length.



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