Unfortunately the dealer wouldn't turn off the continuous reverse beeps for me for free at my 5k checkin. They wanted 60 bucks and I wasn't going to let the stealer make an easy 60 bucks for 1 minute's work. I couldn't find a definitive set of instructions on how to do this using a Mac so I pieced together various articles and here you go:

Buy a ELM 327 Diagnostics cable for about 12 bucks
Go here to download the software
Download Driver Pack 1 and install the 2nd package which is for the most current version of Mac OS/X
Download Driver Pack 2 and install. Reboot after the installation
After you are done, this will enable /dev/tty.usbserial
After you reboot, make sure your car is turned on and plug the connector in. It's right under the dash about 6 inches to the right of the parking break. You can't miss it.
Plug in the USB cable into your MAC
Open up the program "Script Editor"
Copy and paste this:
Code:
tell application "Terminal"
do script with command "screen -U /dev/tty.usbserial 38400"
set number of rows of window 1 to 100
set number of columns of window 1 to 150
set background color of window 1 to "white"
set normal text color of window 1 to "black"
set custom title of window 1 to "keyspan-1"
end tell
Press Compile
Press Run
A terminal window will open
Type the commands below. The line under each command is the response. For instance, simply type "AT H1" and then hit enter. you should see OK. you might only see "K" until you do the second command of "AT L1".
Code:
>AT H1
OK
 
>AT L1
OK
 
>AT SP 6
OK
 
>AT DP
ISO 15765-4 (CAN 11/500)
 
>AT CAF1
OK
 
>AT SH 7c0
OK
 
>21 ac
7C8 03 61 AC 00