How to Check the Production Date of Car Glass?
2 Answers
To check the production date of car glass, look for the trademark in the corner of the glass. It usually consists of several dots and a number. The number represents the production year of the glass. If the dots are on the left side, it indicates the first half of the year, while dots on the right side indicate the second half. Car glass is manufactured by heating the glass in a furnace to near its softening temperature, then rapidly transferring it to cooling zones with varying intensities. This uneven cooling creates different stress levels between the main viewing area and the peripheral areas of the glass. Typically, glass produced using this technology is known as zone-tempered glass.
I always start by looking at the corners of the car window or windshield, where there is usually a small black dot or a code made up of numbers; the dot matrix rule is that the left cluster of dots represents the month (e.g., one dot stands for January), and the right cluster represents the year (e.g., one dot stands for 2021). Some cars use letter formats, such as 'A' representing January. Understanding this is simple: find a clean spot, wipe the glass corner clear, identify the dots, and count them. This helps determine whether the glass is original or matches the car's age, especially when buying a used car—date discrepancies may indicate accident or replacement history, making the purchase more reassuring. Regular checks can also prevent aging issues.
