Does anyone know where parktronic beeper sits in the back?

 

position is shown in the owners manual

the body color circles in the rear bumper are the distance sensors

also look up rear parking sensors in The Mazda accessories catalog under the Technology section to see a photo

 

You misunderstand, it's the sounder I can't find.

 

I see...I would start in the parts catalog such as at this link. I have not really looked for it, but that is where I would start.

Parts Catalog Body