PrePass® Weigh Station Bypass


PrePass® is an automated, state-of-the-art system allowing heavy vehicles that are registered in the program to legally bypass open weigh stations. For questions regarding PrePass®, call 1-800-PrePass (1-800-773-7277) or go to the PrePass® web site at


Transponders: Carriers obtain special transponders used for communication between computers in the weigh stations and the vehicles.

Green signalRed signal

Green Signal: If all requirements for weight, size, safety, etc. are met, the driver receives a green signal that allows the vehicle to bypass the weigh station.
Red Signal: If all requirements for weight, size, safety, etc.are NOT met, the driver receives a red signal which requires the vehicle to go through the weigh station.

Non-PrePass™ vehicles: All heavy vehicles that are not registered in PrePass are required to pass through weigh stations that are open.

Program Statistics: The system has been in operation in California since 1994. Currently, there are 35 weigh stations across California deploying the PrePass™ technology.

How PrePass® Works (JPG): This graphic diagram shows the process of the PrePass™ system.

Bypass Sites Map: This 2.2 megabyte map shows the location of the California PrePass™ sites.

Bypass Sites List: This list includes the location and status of all bypass sites in California. 

How to register for PrePass®: The PrePass™ web site allows you to register easily and learn more about the PrePass™ system.

Contact Information

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