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IIDs are designed to work with most modern vehicles equipped with a standard 12-volt electrical system. However, some categories of vehicles may require some extra attention. The following are some examples : 

  • Classic cars 
  • Vehicles with modified or complex electrical systems 
  • Remote start or push-button ignition 
  • Electric cars 
  • Hybrid vehicles 

A certified Ignition Interlock service provider can offer advice on whether your vehicle requires any special modifications to accommodate the IID.  

Requirements for Ignition Interlocks 

When someone is convicted of a DUI, to reinstate driving privileges, many states require the installation of an IID as part of the rehabilitation process. This allows offenders to maintain limited and monitored driving rights. However, the duration of IID use can vary significantly between states, as each one has different thresholds for requiring vehicle installation based on the severity of the offense, blood alcohol content, and frequency of violations. 

As of 2023, the majority of states mandate the installation of IIDs for every DUI offender, including those convicted for the first time. Specifically, 24 states mandate that individuals install an Ignition Interlock to reinstate driving after a first conviction license suspension. Further, 36 states require similar installation post-driver license suspension for repeat offenders. Six states, including Connecticut, Idaho, New Hampshire, North and South Carolina, and Utah, as well as the District of Columbia, prohibit driving post-DUI conviction for repeat offenders altogether. 

Once an Ignition Interlock Device is installed, a monitoring authority might request the ignition interlock device service provider to share data on BAC levels blown before motor vehicle operation, whether there were attempts to tamper with the IID, and regular maintenance records for the device.  

Given the legal complexities, it’s advisable for individuals required to install an IID to seek legal advice from an attorney. An attorney will provide advice applicable and appropriate to your jurisdiction, your particular situation, and the specific course of action you should follow to regain full driving privileges. 

IID Installation Process 

When you’re mandated to use an IID, you may be questioning how to install an Ignition Interlock device. The following are some steps you might follow to get your IID installed: 

  1. Initial Consultation: Begin with consulting a certified IID provider, such as RoadGuard Interlock. This step involves discussing your vehicle’s make and model, understanding the specific installation requirements, and scheduling an installation appointment. 
  1. Physical Installation: On the installation day, a technician will assess your vehicle’s electrical and ignition systems and connect the IID to your vehicle’s ignition system. This typically involves wiring the device to the car’s ignition, power, and ground circuits. The IID’s control unit is usually placed under the dashboard, while the mouthpiece for breath samples is positioned within the driver’s reach. 
  1. Device Calibration and Testing: After installation, the IID is calibrated to the state-specific BAC limits and other requirements. The technician conducts several tests to confirm the device functions correctly, responding appropriately to breath samples. 
  1. Training and Documentation: The provider will train you on how to use the IID, including giving breath samples and understanding the feedback and signals from the device. You’ll receive documentation of the installation. 
  1. Final Inspection and Approval: A final check is performed to confirm everything is working correctly. Once completed, the vehicle is ready for use with the newly installed IID. 

Compliance Standards for IIDs 

Ignition Interlock Devices (IIDs) must meet stringent standards and certifications regarding their efficacy and reliability. These standards dictate the sensitivity of the devices to accurately measure blood alcohol content (BAC).  

Additionally, the regular maintenance and calibration of IIDs by certified professionals ensure the device accurately detects BAC levels. This assures appropriate function and is vital for upholding the legal and safety objectives of the IID program. 

Benefits of Interlock Systems 

The implementation of Ignition Interlock systems offers significant benefits in enhancing road safety and reducing a DUI offense: 

  • Prevention of DUI Incidents: Requiring a sober breath sample before the vehicle operates directly deters individuals from driving under the influence of alcohol. 
  • Contribution to Road Safety: They reduce the risk of alcohol-related accidents, safeguarding the driver, fellow motorists, and pedestrians. 
  • Promotion of Responsible Driving Habits: Over time, using Ignition Interlocks instills a sense of responsibility in drivers. It encourages a more conscious approach to driving, decreasing the likelihood of future DUI incidents. 
  • Ensuring Legal Compliance and Reducing Repeat Offenses: Studies have shown that Ignition Interlocks effectively reduce a repeat DUI offense, contributing to a safer driving environment. 

Ignition Interlock systems represent a proactive approach to curbing drunk driving. By enforcing sobriety in drivers and fostering a culture of responsibility, these devices significantly contribute to our roads’ overall safety and well-being. 

Steering Towards Safety 

Remember, while Ignition Interlock Devices add a layer of responsibility for the driver, they significantly contribute to safer roads and responsible driving habits. 

If you’re navigating the complexities of an IID requirement, don’t hesitate to seek expert assistance in installing your IID. Visit RoadGuard Interlock, your trusted partner in meeting your Ignition Interlock needs. Learn more and get started on your journey towards responsible driving today. 

The information in this blog is for general informational purposes only. Information may be dated and may not reflect the most current developments. The materials contained herein are not intended to and should not be relied upon or construed as a legal opinion or legal advice or to address all circumstances that might arise. You should contact your attorney to obtain advice with respect to any particular legal matter.  Only your individual attorney can provide assurances that the information contained herein – and your interpretation of it – is applicable or appropriate to your particular situationLinks to any third-party websites herein are provided for your reference and convenience only; Roadguard Interlock does not recommend or endorse such third party sites or their accuracy or reliability. Roadguard Interlock expressly disclaims all liability regarding all content, materials, and information, and with respect to actions taken or not taken in reliance on such. The content is provided “as is;” no representations are made that the content is error-free. 


  1. IIHS. Alcohol interlock laws. 
  1. National Library of Medicine. The Impact of Interlock Installation on Driving Behavior and Drinking Behavior Related to Driving. 
  1. NHSTA. Ignition Interlocks – What You Need to Know.