What to do if ETC was not scanned when exiting the highway after being scanned when entering?

[DeSavannah]

If you used ETC when entering the highway but it wasn't scanned when exiting, the unpaid fee can be deducted together during your next toll station exit. If the toll station cannot resolve this issue, you need to bring your ID card, vehicle license, and OBU device to the local ETC service center for troubleshooting. How ETC works: Through dedicated short-range communication between the onboard electronic tag installed on the vehicle's windshield and the microwave antenna in the ETC lane at the toll station, the system uses computer networking technology to perform backend settlement processing with the bank. This allows vehicles to pass through highway or bridge toll stations without stopping while still paying the required fees. Where ETC can be installed: For small vehicles like cars and minivans, the OBU device is installed on the upper middle part of the front windshield. For large vehicles like trucks and buses, it's installed 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 electronic tag surface and the horizontal plane).