Back to Blog

You have been ordered by the Court in your State to install an ignition interlock device (IID) in your vehicle. The Court has specified how long you will have to use the device. This is required even if you share the vehicle with another driver, so you might be wondering if other people can drive your car with an interlock device. Here is everything you need to know:

In most states, you may share your vehicle with a spouse, partner, or another family member. That person can drive your car as long as he or she performs all required ignition interlock tests. It is, of course, important that you clean the mouthpiece properly before another person uses it. Living with an ignition interlock device will be a way of life for you and other drivers of your vehicle, throughout your ignition interlock requirement period.

This means other people using the vehicle will also need to learn how to properly operate ignition interlock devices. Luckily, RoadGuard Interlock devices are easy to use.

Other Drivers

Although you may be the primary driver of a household vehicle, circumstances may make it necessary for a family member to use your vehicle. That person must have a driver’s license, valid insurance, and be sober when driving.

In addition to family members, an auto repair shop may have to drive the car a short distance. The repair person should be notified and instructed on how to operate the ignition interlock device.

How Do Ignition Interlock Devices Work

If you are wondering how do ignition interlock devices work, rest assured. RoadGuard Interlock devices guide you with step-by-step messaging on how to provide a correct breath sample. Start your car and your device will power up. Take a deep breath in. Blow steadily into the device mouthpiece. Do not remove your mouth from the mouthpiece, and when the tone changes, take a deep breath in again. Your breath sample result will appear in seconds. If your breath sample result shows a Breath Alcohol Concentration (BrAC) below the set threshold, then the Interlock test has passed, and you’re free to go! If your BrAC exceeds a specified level, the ignition interlock device temporarily prevents your vehicle from starting. It is important to remember that some alcohol-containing foods, beverages, and even the alcohol content in mouthwash may affect your breath sample and, thus, interfere with the ignition interlock device test results. Keep products containing alcohol like hand sanitizer, mouthwash, hairspray, perfume, etc. away from the device. Do not consume any food, beverages (other than water), or tobacco products, within 15 minutes before providing a breath sample.

State Laws

Most States will allow another driver to use your vehicle. They may be a designated driver for you, your friends, or another family member.  Other drivers can use your car, but they too should only ever drive when sober.

IMPORTANT NOTE:  You cannot ask or allow someone else to blow into the interlock device and then take over driving the vehicle yourself under any circumstance. This is one of the most severe ignition interlock violations, and there may be serious consequences for this type of violation, including, but not limited to, suspension of your restricted driver’s license or it may be deemed a violation of your bail or probation conditions. Additionally, your ignition interlock requirement period can be extended, or you may be fined or confined in jail for this, or other ignition interlock violations.

Personal Responsibility

Do not be embarrassed about using an ignition interlock device when another person must drive your vehicle. This device allows you to continue driving as long as you are sober. This shows that you are now aware of the dangers of drunk driving and that you are on the road to becoming a responsible driver.

We want to help you feel confident about using your ignition interlock device. Our devices are backed by an extensive network of service centers with qualified technicians who will show you how to safely use this device. Contact us today for more information.

*Links to any third-party websites herein are provided for your reference and convenience only. RoadGuard Interlock did not create nor develop and does not own any such third-party websites. RoadGuard Interlock does not endorse nor support the content of, nor any opinions stated in any such third-party website links. RoadGuard Interlock is not responsible for the content of any third-party website or its accuracy or reliability. Nothing contained in this article or in any such third-party website shall be considered legal advice or be deemed to constitute legal advice. For any legal advice concerning a DUI arrest, charge, conviction, or consequences thereof, you should contact an attorney of your choice.