AVI Devices

AVI devices emit a signature (the device number) that is detected by an antenna mounted over the drive lane. The signature is authenticated by the associated database where access privileges are established.

For reliable use, AVI devices must be mounted on vehicle front windshields (see diagram below).

  • Devices displayed in any other fashion will be out of alignment with antennas and will not work properly.
  • AVI devices also function as parking permits and must be visible to enforcement officers.

Install the AVI devices using the Velcro™ adhesive strips provided. Place the AVI device horizontally in the lower left-hand corner, approximately two inches away from window frames:

  • AVI devices are transferrable between the user’s vehicles. Additional Velcro™ is available upon request to the Parking Customer Services office.
  • AVI devices are horizontally polarized and will not work correctly if mounted vertically.
  • AVI devices should not be placed too close to window frames as the metal may interfere with communication between the device and antenna.
  • Some vehicles have special features such as heat elements, infrared reflection, or metal imbedded in the windshield glass that will deflect the AVI signal and prevent it from being read by the AVI antenna.
AVI Placement

Approach gates slowly. Although AVI devices are very quickly authenticated, the gate is mechanical and requires a few seconds to respond. If a vehicle approaches the gate too quickly, the antenna may not pick-up the device signature. Boxes mounted near the AVI antennas on the ceiling are equipped with LED lights that will illuminate to verify when devices have been read by the antenna.

Do not tailgate vehicles as the vehicle in front may obstruct the signal path between your AVI device and the AVI antenna mounted in the lane. Allow a safe and reasonable distance – half a car length -- between yourself and other vehicles.

Access Problems

If you experience problems while using an AVI device, contact the AVI Assistance Line at (734) 763-5555 or Parking Customer Services at (734) 764-8291.