Is it mandatory to install ETC on the windshield?

[LeAutumn]

ETC can be used without being attached to the glass. Installing ETC on the upper part of the windshield is to minimize obstruction of the driver's view while ensuring better recognition by the equipment at highway toll stations. If you prefer not to install it on the glass, place it in an open area where it can be seen through the windshield. For small vehicles, the ETC is generally installed in the upper middle part of the front windshield, while for large vehicles like trucks and buses, it is installed in the lower middle part. The suitable installation height is between 1.2 meters and 2.5 meters, with an installation angle between 30 to 90 degrees. If the vehicle has or will have a blast-resistant film, which may interfere with microwave signal transmission, the ETC should be installed in the microwave window strip. Here are some considerations for ETC installation: Avoid obstructing the view—best installed behind the rearview mirror: Many car models have windshields with a steep incline, which can reduce the driver's field of vision. Installing the ETC without considering this may increase blind spots. Placing it behind the rearview mirror on the right side helps avoid blocking the view. Ensure unobstructed charging: The ETC electronic tag consumes power but generally does not require charging or battery replacement, as it has a built-in solar panel for self-charging. Therefore, avoid installing it on the windshield's blacked-out areas or positions that might block the solar panel. Do not remove it once installed: The adhesive backing has an anti-tamper button connected to a switch. Once installed, the windshield presses this button in. If removed, the button pops out, triggering the switch and locking the tag, rendering it unusable until unlocked at an ETC service point. This mechanism prevents multiple vehicles from sharing one device. ETC usage tips: The ETC transaction sensing range is 8 meters. To avoid paying for the vehicle ahead due to its faulty ETC device, maintain a distance of over 10 meters. The ETC lane recognition speed is 20 km/h—exceeding this may result in failed transactions. If using a debit card-linked ETC, insufficient balance will cause transaction failures.

[Dallas]

Many people think the ETC device must be mounted on the windshield, but that's not necessarily true. It was originally designed to be installed near the rearview mirror on the windshield mainly for optimal signal reception and solar charging convenience. However, some car owners have successfully placed it on the dashboard center console – I've personally tested putting it in front of the instrument cluster and it worked fine at toll gates without issues. The key is ensuring the little black box gets sufficient sunlight for charging, and the position doesn't obstruct the driver's view. For those concerned about aesthetics, using a bracket to secure it in the dashboard crevice is also viable. The most critical installation requirement is avoiding metallic window tints – those metal-coated films will block signals, which matters more than the positioning. Regularly checking the device's battery level is advisable though, since charging efficiency may decrease when not mounted directly on the glass.

[Lilian]

I remember pondering this issue when helping a friend install an ETC last time. The windshield position is indeed the most ideal, as the solar panel can charge fully and the signal reception is most stable. But in reality, as long as the device's front faces the direction of the toll station, placing it on the dashboard or center console still works fine. I personally placed mine on a platform near the air vent, and it has never failed in over two years. Just be careful not to block the device with items like tissue boxes, as it may cause sensing failures. For owners with metal film, it's recommended to place it directly on the sunroof, since front windshield films most affect signal penetration. If you really don’t want to stick it to the glass, it’s best to buy a new model with a backup battery to avoid charging hassles.

[LePhoebe]

ETC devices are most commonly stuck on the windshield for solar charging and clear signal transmission. But in reality, it's much more flexible: some people use 3M adhesive to attach them to the dashboard, I've seen the bizarre move of clipping them to the sun visor, and others specifically buy magnetic mounts for fixation. The key points are just two: the device can get sunlight for charging and isn't blocked when passing through toll stations. At highway toll booths, it's common to see car owners with the device placed on the center console still passing through the gate instantly. If your front windshield has a metal film, don't stick it on the glass—the signal will definitely be interrupted. After choosing a spot, it's best to test it a few times to avoid the embarrassment of being stopped at the toll gate.