2009 Mazda RX-8 Key Fob Programming

You can add a new key to this Mazda yourself if you already have two keys that start the engine. The new key must be cut first, and it has to be a genuine key — a cloned hardware-store key won't work.

1. 1Insert one working key and turn it to ON (just shy of starting). Hold it there about 3 seconds, until the security light goes out.
2. 2Turn back to OFF and remove the key.
3. 3Within 10 seconds, insert the second working key and turn to ON. Again wait about 3 seconds until the security light goes out, then turn OFF and remove it.
4. 4Within 20 seconds, insert the new key and turn to ON. Hold for at least 3 seconds, then turn back to OFF.
5. 5The security light comes on for three seconds — that confirms the new key is programmed.

Your 2009 Mazda RX-8 key fob uses a CR1620 3V lithium coin cell. A fresh one typically lasts 3–5 years.

How to replace the battery

1. 1 Look for a small notch or screw on the side of the fob where the key blade meets the buttons.
2. 2 Pry the housing apart with a coin or small flathead (or remove the screw).
3. 3 Pop out the old coin cell, noting its orientation.
4. 4 Insert the new battery the same way up, then snap the case shut.
5. 5 Test the buttons — if they work, you're done.