First of all I did not apply a firmware update since a long time. Seem to suggest that it is an issue with an incorrectly applied firmware update.

After some wait time and after some hard reboots the system powers up normally. The Power LED will flash and the system sounds 9 beeps (3short, 3long, 3short). Just now after owning/using the device for 8 month the 9 beeps issue appeared: Occasionally the MBP will not start up (no fanfare Mac Startup sound). System Software was always kept up to date - EFI Firmware update 1.6 was applied when it came out ~ 4month ago. Here are my thoughts on this issue so far: I have just found this Thread - I have a very similar Mac and the exact same issue. Im thinking of doing an archive install, as that was another suggestion to make sure firmware is all up to date and being used correctly. Another interesting detail is that this seems to only occur when the computer is booting under battery power, which makes it seem like a battery firmware issue, specifically. Also, if I look for the firmware restoration CD as suggested in more than one thread at, there is no such download for the macbook5,1. As far as I or Software Update can tell, all firmware is up to date. In reading here and in the Apple discussion forms, there seem to be a few conflicting ideas as to what it is, although I believe the most accepted is it being some sort of firmware update issue. Following the beeps, the computer will boot normally after several seconds. I recently had my computer out, started it up, and instead of the startup dong I received 9 very harsh sounding beeps in series, 3 short 3 long 3 short (much like SOS in morse code). Ive got a fairly vexing problem here.I'm on a 15' 2.53Ghz MBP (late 2008 unibody).

Macbook pro 3 beeps no startup