It’s important to mount your PrePass® transponder to ensure accurate reads and uninterrupted bypassing at weigh stations and use at toll facilities. Whether you’re using a standard transponder, a PrePass Plus device, or the mobile app, following the right steps will save you time and help avoid costly violations. 

Key Things to Remember

  • Do not move your transponder to another vehicle without notifying PrePass Customer Support. 
  • Only one PrePass-issued device should be installed in each vehicle. 
  • Return all unused devices to PrePass. 
  • Report lost, stolen, or damaged devices by logging into your account at My PrePass or calling Customer Support at 1-800-PREPASS (773-7277). 
  • Use both the PrePass Mobile App and a transponder for the best chance at receiving bypasses at fixed and app-only sites. 
  • Download the PrePass Mobile App for Android or iOS. 

Where to Mount Your PrePass Transponder

PrePass transponders are designed to attach to the inside of your windshield using the provided adhesive Velcro strips. Keep in mind: 

  • Do not use glue or adhesives other than the provided Velcro. 
  • Mount the device where the driver can easily see it without obstructing their view of the road. 
  • If your windshield is curved, you can order additional Velcro strips free of charge from PrePass. 

Installation Instructions by PrePass Device 

PrePass Transponder 

  • Transponder must be mounted two inches to the right or left of center and at least two inches (but not more than three inches) from the top of the windshield, or with a two-to-three-inch clearance above the dash. 
  • We recommend the lower placement, especially for trucks with visors and/or overhangs. 
  • The transponder must be positioned so the PrePass label and red and green lights face the driver. 
  • Note: If your transponder is currently placed high on the windshield and you are successfully receiving signals, there is no need to move it to the lower placement position 

Fusion Transponder (PrePass Plus) 

  • Transponder must be mounted two inches to the right or left of center and two inches (but not more than three inches) from the bottom of the windshield. 
  • Transponder must be positioned so the PrePass label and lights are visible to the driver. 
  • Note: If your truck has a right fender spot mirror, we recommend placing it to the left of center to prevent blind spots for that mirror. 

PrePass Mobile App on a Mobile Phone or Tablet 

  • When using the PrePass Mobile App on a mobile device, you may mount the device from the floor, dash or windshield. 
  • Consider locations convenient to the driver’s line of sight. If placed on the windshield, according to FMCSA it must be: 
  • “Mounted not more than 100 mm (4 inches) below the upper edge of the area swept by the windshield wipers, or 
  • Not more than 175 mm (7 inches) above the lower edge of the area swept by the windshield wipers, and outside the driver’s sight lines to the road and highway signs and signals” 

ElitePass Transponder (PrePass Plus) 

  • Transponder must be mounted two inches to the right or left of center and two inches (but not more than three inches) from the bottom of the windshield. 
  • Transponder must be positioned so the PrePass label and lights are visible to the driver. 
  • If your truck has a right fender spot mirror, we recommend placing it to the left of center to prevent blind spots for that mirror. 
  • When replacing batteries, use two (2) AAA lithium batteries. 

Toll Sticker Tag 

  • If using a sticker transponder, carefully peel the backing from the sticker. 
  • Avoid touching the adhesive and keep the sticker as flat as possible and avoid bending it as it may break the antennae. 
  • Place the sticker transponder in one of these locations: 
  • Lower left-hand or right-hand corner of the inside of the windshield, or 
  • Place it behind the rearview mirror on the inside of the windshield 

Mounting Procedure 

  1. Before securing the transponder onto the windshield, make sure the area has been thoroughly cleaned. 
  1. Remove the backing tape from the Velcro adhesive strips provided and firmly press the transponder onto the interior windshield surface so that the adhesive affixes to the glass. 
  1. Do not glue transponders directly to the window. 

Why Proper Mounting Matters for your PrePass device

Improperly mounted devices may not be read correctly, which could result in your vehicle not bypassing or being issued violations at PrePass locations. 

Do not remove the Velcro adhesive strips from your windshield or transponder and reuse them. If you need additional Velcro adhesive strips or have questions or problems installing your transponder, please call PrePass Customer Support at 1-800-PREPASS (773-7277).