No.1 Additional Key Programming Procedure (Using Two Valid Keys): Procedure

WARNING: This page is about a different car, the 2007 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Valid Key And Key For Registration

Courtesy of MAZDA MOTORS CORP.

Prepare key 3 for programming.
Start the engine using key 1.
Verify that the security light illuminates for approx. 3 s , and then goes out.
Turn the ignition switch to the LOCK position.
Using key 1, turn the ignition switch to the ON position.
Verify that the security light illuminates for approx. 3 s, and then goes out.
Using key 1, turn the ignition switch to the LOCK position within approx. 4 s after the security light goes out.
Remove key 1.
Repeat Steps 2-5 using key 2 instead of key 1.
Repeat Steps 5-8 using key 3 instead of key 1.
If additional keys need to be programmed, repeat Steps 1-10, and replace key 3 in Step 10 with the key to be programmed (key 4).