In your car
6 small things in your car, explained
The arrow on the fuel gauge, the black dots on the windshield and the numbers on your tires all mean something.
By the Rmmxp editors · Updated November 6, 2026 · 6 items · 2 min read
The fuel door arrow
Where to look: Next to the fuel icon on the gauge.The small triangle points to the side where the fuel door is.
The black frit band on the windshield
Where to look: Along the edge of the glass.It helps the adhesive grip and protects it from sunlight. The fading dots make the edge look smoother.
The thin lines across the rear window
Where to look: On most rear windows.They are defroster elements. A small electric current warms them to clear frost and fog.
The tire's DOT date code
Where to look: Last four digits on the sidewall.Week and year of manufacture: 1525 means the 15th week of 2025.
The size numbers on the tire
Where to look: For example 225/60R17.Width in millimeters, sidewall height as a percentage of the width, radial construction, and wheel diameter in inches.
The small sensor on the dashboard
Where to look: A little dome near the windshield on many cars.On many cars it is a light sensor that helps automatic headlights and dashboard brightness respond to daylight.
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