{"id":286703,"date":"2016-04-04T10:45:08","date_gmt":"2016-04-04T15:45:08","guid":{"rendered":"https:\/\/content.findlaw-admin.com\/ability-law\/dui\/cases\/ignition-interlock-devices.html"},"modified":"2025-08-14T13:53:32","modified_gmt":"2025-08-14T18:53:32","slug":"ignition-interlock-devices","status":"publish","type":"page","link":"https:\/\/www.findlaw.com\/dui\/cases\/ignition-interlock-devices.html","title":{"rendered":"What Happens If You Fail an Ignition Interlock Test?"},"content":{"rendered":"\n
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What Happens If You Fail an Ignition Interlock Test? <\/h1>\n\n
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\n By Balrina Ahluwalia, Esq.<\/a> | Legally reviewed by Laura Temme, Esq.<\/a>\n | Last updated\n
\n \n <\/i>\n Legally Reviewed\n <\/summary>\n\n
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This article has been written and reviewed for legal accuracy, clarity, and style by FindLaw\u2019s team of legal writers and attorneys<\/a> and in accordance with our editorial standards<\/a>.<\/em><\/p>\n\n <\/div>\n <\/details>\n\n

\n \n <\/i>\n Fact-Checked\n <\/summary>\n\n
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The last updated date refers to the last time this article was reviewed by FindLaw or one of our contributing authors<\/a>. We make every effort to keep our articles updated. For information regarding a specific legal issue affecting you, please contact an attorney in your area<\/a>.<\/em><\/p>\n\n <\/div>\n <\/details>\n<\/section>\n\n\n

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Key Takeaways<\/h2>\n

A failed ignition <\/span>interlock test<\/span> occurs when the device detects a breath alcohol concentration above the preset limit, typically 0.02%. This results in vehicle lockout<\/span>, test recording, and violation reporting to monitoring agencies like courts, DMVs<\/span>, or probation officers<\/span>. Consequences can include extended IID<\/span> requirements<\/span>, license suspension<\/span>, or additional penalties. But, you can challenge false positives through formal hearings, appeals, or program modifications with proper documentation and evidence.<\/p>\n\n <\/div>\n <\/div>\n<\/div>\n\n\n

You probably weren\u2019t thrilled about having an ignition interlock device (IID) installed in your car. But at least you could maintain your freedom. You just had to play by the rules \u2014 which you did. So why is your IID reporting that it detects alcohol? Or maybe you had a drink but expected to be well below the limit. Whatever the circumstances, an IID test that detects alcohol can be a scary thing.<\/p>\n

In this article, we explore some of the common implications of a failed ignition interlock test. We\u2019ll also discuss some of the legal principles behind challenging these test results. State law generally governs in this area, so the specifics can vary by jurisdiction<\/a>.<\/p>\n

If you\u2019re not quite sure about your next steps after a failed IID test, consider speaking with an attorney licensed in your state<\/a>. Many specialize in matters related to driving under the influence (DUI) or driving while intoxicated\/impaired (DWI) charges. A DWI\/DUI attorney<\/a> can help you understand your options at this uncertain time.<\/p>\n

What Is an Ignition Interlock Device?<\/h2>\n

An IID is a small machine installed in a vehicle to help prevent drunk driving. It works like a breathalyzer. Before starting the car, the driver must blow into the device. If it detects alcohol above a certain breath alcohol concentration (BrAC) limit (usually around 0.02%), the car won\u2019t start. This is much lower than most states\u2019 legal limit<\/a> for blood alcohol concentration (BAC) of 0.08%.<\/p>\n

If the driver\u2019s breath sample shows a BrAC below the preset limit, the device will allow them to start the vehicle. IIDs can also conduct random rolling retests while a car is running to make sure the driver is still sober.<\/p>\n

When Are IIDs Used?<\/h2>\n

Ignition interlock devices are often court-ordered for people who have been convicted of DUI\/DWI offenses<\/a>. Some states\u2019 departments of motor vehicles (DMVs) can require an IID even if the court doesn\u2019t.<\/p>\n

For example, a DMV may impose an ignition interlock device requirement after a DUI\/DWI conviction or administrative license suspension.<\/p>\n

What Happens If an IID Detects Alcohol?<\/h2>\n

If an IID detects alcohol on your breath <\/a>that\u2019s over the preset limit, it will:<\/p>\n