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
Operational Inspection: Notes
- Switch the ignition ON (engine off or on).
- Move the vehicle to a place with a showroom level of brightness.
- Verify that the indicator light is illuminated.
- Verify that the indicator light switches when the auto-dimming mirror on/off switch is pressed.
- While the indicator light is illuminated, verify that the mirror surface brightens.
- Cover the front light sensor with a hand and verify that the mirror surface darkens when light is shone on the rear light sensor.
- Remove your hand covering the front light sensor and verify that the mirror surface brightens.
- If the auto-dimming mirror does not operate, inspect the terminal voltage. (See TERMINAL VOLTAGE TABLE (REFERENCE) .)
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.