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: Disassembly

Remove the lower cover while pressing the knob in the direction of the arrow.

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Press in the tab to unlock the upper cover.

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Insert a tape-wrapped flathead screwdriver into the gap and slide it in the direction of the arrow.

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Twist the flathead screwdriver in the direction of the arrow and remove the upper cover.

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Remove the cap using the tape-wrapped flathead screwdriver.

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Remove the battery using tape-wrapped flathead screwdriver.

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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.