Interior Mount Transponder: What Is It?

The E-ZPass transponder is a free standard model that is applicable in 18 states in the United States. To receive the lowest tolls for your account, drivers should mount their E-ZPass transponder on the interior of their vehicle. To install the interior E-ZPass transponder, sit inside your vehicle facing forward and select a location between the exposed edge of the windshield (roofline) and the rear view mirror. Clean and dry the interior of your windshield around the rearview mirror without removing the self-adhesive strips from the back of the transponder.

For proper operation, make sure the transponder is mounted as follows: identify the front face of the transponder, which displays the E-ZPass label and two arrows on the transponder. Janus interior transponders mount to the inside of the vehicle windshield using 3M™ Dual Lock™ fasteners, while FME transponders programmed for rooftop must be mounted on the roof of the vehicle. The mounting location must provide direct line-of-sight communication.

E-ZPass uses a vehicle-mounted transponder activated by an antenna on a toll lane, with your account information stored in the transponder. The HOTPass® interior transponder mounts on the vehicle windshield, with the preferred location between the roofline and the rear view mirror post. The most common type is the interior transponder, which is mounted on the inside of your windshield.