Skeletonized key

When I bought my 2 used, it came with only one key, which looked like it had been chewed up by a dog.

I had a proper switchblade fob made as well as another plain key. Today I decided to see what was inside the chewed up key, possibly make a screwdriver handle key with the transponder embedded in the handle. This is what I found inside:



Unfortunately it won't start the car like that - not without the little black wedge-shaped transponder. But it looks like some of the aftermarket keys I've seen for non-immobilizer cars. Really cool.

I'm thinking of popping the stitching out of that leather Mazda keychain on the right and slipping the transponder inside. Think that hanging off the skeletonized key would be close enough proximity for the transponder to work?

The transponder needs to be within 2cm or so of the plastic ring around the key insertion point on the steering column. There's no harm in trying; the car just won't start if it doesn't detect the transponder.

Just to confirm -- is the transponder the black piece at the corner of the white plastic trim?

Yep. You can actually buy the chips in bulk, they're called a "4D63" 80-bit transponder.