AIX 5.1 Box not booting

Quick backgound. We just moved the Datacenter. I attempted to boot one of our older AIX machines backup and it stops at a 518 Error code. Which is fine I need to run fsck on the volumes. The issue is I can't find the original media with the appropriate Date that was originally installed(previous admin installed and I'm not sure even which version is installed 5.1 or 5.2). I have put in another AIX 5.1 CD1 and 5.2 CD1 tried to boot off of that into Maintenance Mode. It doesn't do it. Is there another way to run fsck without a mksysb tape or the original CD, or can I make a mksysb tape from another machine? Shouldn't the box be able to boot off any 5.1 CD1 or a 5.2 Cd1 to get maintenance mode. It appears to try and boot off the CD by reading it numerous times, but never goes to the Maintenance Menu after I push 5 at the beep. Any assistance would be appreciated.

Try key F1(maybe F2 or F5) or for older reset