why does my new mdx sometimes give a series of beeps when i lock it.

 

Welcome to the forums.

This thread has been moved from the 1G TSX Problems & Fixes Forum to the appropriate subsection that is applicable to your post.

 

Is the key in your pocket or hand and you simply walk away using the autolock convenience? A series of fast beeps when walking away means your key is out of range...you're too far away when the last door closed...i.e. the lift gate closed.
When this happens you'll need to use the button on the remote to lock the vehicle. This often happens to me when I hit the button on the liftgate and walk away. I walk faster than the gate closes, so the key is out of range by the time the car wants to lock.