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.

2021 Mazda 3 BaseFACTORY OEM SERVICE PROCEDURE

Remote Transmitter Disassembly/Assembly: Assembly

Insert a new battery (CR2032) into the remote transmitter so that the positive pole is facing up.
Install the cap.

Courtesy of MAZDA MOTORS CORP.
Install the upper cover.

Courtesy of MAZDA MOTORS CORP.
Insert the tabs of the lower cover into the slots of the remote transmitter and install the lower cover.

Courtesy of MAZDA MOTORS CORP.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.