Can ETC be attached at the black dot area on the windshield?
3 Answers
The black dot area on the car's windshield should not be used for ETC installation, as this position may obstruct the solar panel behind it from receiving sunlight. Additionally, the chosen ETC installation location must not interfere with the driver's line of sight. Where can ETC be installed: For small vehicles such as cars and minivans, the OBU device should be installed on the upper middle part of the windshield. For large vehicles like trucks and buses, the installation position is on the lower middle part. ETC installation requirements: The height should be no less than 1.2 meters and no more than 2.5 meters; the installation angle N should be between 30º and 90º (the angle between the surface of the electronic tag and the horizontal plane). The ETC installation process is as follows: Upon receiving the device, first check if the ETC card and electronic tag (OBU) are damaged. Press the anti-tamper button on the back of the OBU, and a red light will briefly illuminate. The OLED screen will display "Tag Invalid" or "Please Insert Card," indicating the device is functioning properly. Clean the windshield to ensure the surface is smooth, clean, and dry. Then peel off the adhesive backing of the OBU and attach it to the installation position. Press firmly for 2-3 minutes to remove any air bubbles. Insert the ETC card with the front side facing the driver and the back side facing the windshield, ensuring the chip is properly inserted into the OBU device.
I’ve tried cutting corners by sticking my ETC device directly onto the black dots on the windshield several times, only to end up with it falling off or malfunctioning. Those black dots are actually dotted patterns near the edges of the windshield, primarily for sunshade purposes. Their uneven surface or special coating makes adhesive tape unreliable, and ETC signals can also be affected. Later, I looked it up and learned the correct method: clean the central area of the glass thoroughly to ensure no dust or grease, then find a smooth spot to attach it firmly. Since ETC relies on wireless signals for toll collection, an off-center or unstable position can delay highway passage—something worth paying attention to. When installing a new device, it’s best to pick a clear, dry day for the job, as lower humidity ensures stronger adhesion and avoids repeated adjustments. Over time, windshield wear may also impact signal performance, so it’s wise to periodically check the device’s placement.
Those black dots are actually part of the windshield design, typically used for sun protection or edge reinforcement, but they're not suitable for mounting ETC devices. Since ETC operates via radio frequency signals (similar to WiFi or Bluetooth), the black dots may contain metal particles or special materials that can interfere with signal transmission, leading to recognition failures. I personally tried mounting it there and always experienced delays at toll booths, which was quite inconvenient. The standard installation position is on the flat area directly in front of the windshield or near the rearview mirror – clean the surface with alcohol first and press firmly for 30 seconds to secure it. Also, avoid placing the ETC too high as it may obstruct your view and compromise driving safety. These small details actually make a big difference in practice. I recommend testing the signal response by driving a short distance after installation.
