Repeating tone with 3 seconds pauses on basic Macbook 2009

[themamba24]

I disassembled my 2009 mac book was so I could replace the LCD (cracked) with the LCD screen of my 2006 macbook which I dont currently use.

(I now realize that I shouldn't have even touched the logic board in the swap but that's not relevant at this point).

Now that I have reassembled both with the swapped screens my 2009 mac book (with 2006 LCD) won't start up and instead has a repetitive tone/beep (in sync with a flashing light) with 3.5 second pauses in between each tone. What problem is this an indication of for a 2009 basic macbook?

 

[Dave Braine]

This seemed to work for someone with the same fault:
http://forums.formaceyesonly.com/index.php?topic=424.0

 

[retroneo]

Double check there is known good RAM present and that it is installed securely.

For specifics of the error tones:

See http://support.apple.com/kb/HT2341