Driver Services

Ignition Interlock

Certified Ignition Interlock Program

When Arizona law mandates use of an interlock following a period of driver license suspension/revocation, you must have one installed by an MVD-authorized company and provide proof of the installation.

MVD uses special forms and procedures to monitor drivers required to have the device installed. You may be issued a replacement driver license containing the words "Ignition Interlock" and mark your record so that law-enforcement officers will be aware of the interlock requirement if you are stopped.

Please Note: Your Arizona Driving Privileges must be reinstated in order to establish a starting point for your required ignition interlock time frame. To reinstate, please visit an MVD or Authorized Third Party office.

How It Works

An ignition interlock is a breath-analyzing device that is wired to the vehicle's ignition and installed on the vehicle dashboard. Before the vehicle can be started, the driver first must exhale into the device. If the interlock detects alcohol on the breath, the engine will not start.

At random times after the engine has been started, the device will require the driver to provide another breath sample. If it isn't provided, or the sample exceeds a set blood alcohol level, the device will log the event, warn the driver and then start an alarm (e.g., lights flashing) until the ignition is turned off, or a clean breath sample has been provided.

For safety reasons, the device cannot turn off the car ignition once it has been started.

Interlocks Help to Prevent Drunk Driving

The International Council on Alcohol, Drugs and Traffic Safety maintains that interlocks, when combined with a comprehensive monitoring and service program, lead to a 40-95 percent reduction in the rate of repeat drunk driving offenses, as long as the device remains on the vehicle.

Ignition Interlock Overview

Civil RightsTitle VI of the Civil Rights Act of 1964, and the Americans with Disabilities Act (ADA)
  • Pursuant to Title VI of the Civil Rights Act of 1964, and the Americans with Disabilities Act (ADA), ADOT does not discriminate on the basis of race, color, national origin, age, sex or disability. Persons that require a reasonable accommodation based on language or disability should contact ADOT’s Civil Rights Office at 602.712.8946 or at Requests should be made as early as possible to ensure the State has an opportunity to address the accommodation.
  • De acuerdo con el título VI de la Ley de Derechos Civiles de 1964 y la Ley de Estadounidenses con Discapacidades (ADA por sus siglas en inglés), el Departamento de Transporte de Arizona (ADOT por sus siglas en inglés) no discrimina por raza, color, nacionalidad, edad, género o discapacidad.  Personas que requieren asistencia (dentro de lo razonable) ya sea por el idioma o por discapacidad deben ponerse en contacto con la Oficina de Derechos Civiles al 602.712.8946 o en Las solicitudes deben hacerse lo más pronto posible para asegurar que el equipo encargado del proyecto tenga la oportunidad de hacer los arreglos necesarios.