Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2007 Mazda CX-9 V6-3.5LFACTORY OEM SERVICE PROCEDURE
Advanced Keyless System
CARD KEY BATTERY REPLACEMENT [ADVANCED KEYLESS SYSTEM]

1. Pull out the auxiliary key

2. Replace the cap using a flathead screwdriver, then rotate and remove the cap.
CAUTION: Do not turn the cap excessively. The cap may be damaged.

3. Insert a flathead screwdriver into the crack and press the battery out.

4. Insert the new battery (CR2025) with the positive pole (+) facing the (+) mark on the cap.
Battery specification : Lithium CR2025 x 1
NOTE: The batteries will last about 1 years when used 10 times a day.

5. Rotate and close the cap.
6. Reinsert the auxiliary key.
1. Pull out the auxiliary key
2. Replace the cap using a flathead screwdriver, then rotate and remove the cap.
CAUTION: Do not turn the cap excessively. The cap may be damaged.
3. Insert a flathead screwdriver into the crack and press the battery out.
4. Insert the new battery (CR2025) with the positive pole (+) facing the (+) mark on the cap.
Battery specification : Lithium CR2025 x 1
NOTE: The batteries will last about 1 years when used 10 times a day.
5. Rotate and close the cap.
6. Reinsert the auxiliary key.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
