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What Is an Ignition Interlock Device? 

If you have been convicted of a DUI, you may be required to get SR-22 insurance before you can get your license back. But did you know that some states require you to install an ignition interlock device at your own expense as well? 

This article walks you through everything you need to know about interlock devices, including how they work, how much they cost and where to get one. 

What Is an Ignition Interlock Device (IID)? 

An ignition interlock device (IID) is a special type of breathalyzer that’s installed in your car. It’s connected to the car’s starter and won’t allow you to start the engine unless you blow into it and test within the acceptable blood alcohol content (BAC) limit. 

As with SR-22 requirements, each state sets its own rules about who can get back on the road with an interlock device. Some states require an IID for repeat offenders, while others require it after your first DUI conviction. 

How Much Does an IID Cost? 

Installing an ignition interlock device typically costs between $70 and $150. Since most people don’t plan to use an IID permanently, it’s more common to lease a device, which might cost between $60 to $90 per month. This includes required monthly reporting by the manufacturer, as well as any additional technology (cameras, GPS, etc.) that are required in your state. 

Of course, this is all in addition to the higher cost of SR-22 insurance that you’ll need to carry while you have your IID. If you can’t afford the cost of an interlock device, some states offer financial assistance. It’s also possible to get an exemption from a doctor or employer, but this is very rare. 

Where to Get an IID 

Your state’s DMV site will contain more information about where to get an IID, including a list of approved manufacturers. Some of the biggest IID manufacturers include: 

  • LifeSaver 
  • Intoxalock 
  • Draeger 
  • Alcohol Detection Systems 
  • Smart Start 

Each manufacturer has a network of certified technicians who can install and calibrate your interlock device. As you shop around for the best manufacturer, make sure that they have conveniently located technicians because you’ll need to calibrate the device several times per year. Remember that forgetting to calibrate your device can be just as bad as driving without SR-22 insurance. 

How Much Can You Drink With an IID? 

The legal BAC limit for drivers is 0.08%, but the rules are different for IIDs. In some states, you won’t be able to start your car if your BAC is as low as 0.02%. That equates to just one drink. 

Interlock devices can log how many times someone unsuccessfully tries to start the car. If there are too many failed attempts within a short period, then the device will completely lock down for 24 hours. So, always make sure you’re sober before blowing into your IID! 

What It’s Like to Drive With an IID

When most people think of interlock devices, they imagine blowing into the device and driving normally after that. But starting your car is only the beginning. 

In most states, you’ll need to pass random breathalyzer tests while you’re driving (these are known as “rolling retests”). The purpose of a rolling retest is to make sure you’re not drinking and driving or that someone else blew into your device to start your car. Keep in mind that it’s illegal to have someone else test for you, and many modern devices come with cameras and facial recognition systems to make sure you’re compliant. 

Your device will alert you when it’s time for a retest, and you’ll have a few minutes to safely pull over to blow into the IID. If you fail the test, the device will log the violation, and you’ll face stiff penalties later. 

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Can Anyone Drive Your Car If It Has an IID? 

Technically, anyone is allowed to drive a car with an IID installed. However, they’ll need to blow into the IID to start the car. Keep in mind that the acceptable BAC limit will apply to anyone who drives your car. So, if a friend has had a drink or two, they may fail the IID test, even if they’re technically within the legal BAC limit. 

Can You Drive Anyone Else’s Car If You Need an IID? 

Your requirement to use an IID applies to any car you drive — not just your own. So, if you want to drive your friend’s car or even your spouse’s car, they’ll need to have an IID installed before you can legally use it. That’s a big favor to ask of someone, especially since they’ll need to blow into the IID to start their car. 

If you need an IID, it’s better to plan on using your car for a while. But if you do end up using someone else’s vehicle, make sure that you have the right type of SR-22 insurance as well. 

What Information Does the DMV Get from an IID? 

An ignition interlock device can store a lot of information to make sure you’re driving safely and staying in compliance with your IID program. When you take your car in to calibrate your device, the technician will download the latest data, including: 

  • Times when you blow into the device (along with your BAC level) 
  • How long you drive 
  • Results of rolling retests 
  • Photos confirming who blows into the device 
  • In some states, location and GPS data 
  • Whether anyone tried to remove or tamper with the device 

The technician or device manufacturer will send this information to your state DMV. So, if you violate the terms of your IID agreement, you may not be caught immediately, but the DMV will eventually find out. 

Also, remember that full compliance also includes having SR-22 insurance for as long as required. Otherwise, your insurance company will be the one to contact the DMV about your violation. 

Penalties for IID Violations

Keep in mind that it’s a privilege to be allowed to drive with an IID, and the alternative is not being allowed to drive at all. That’s why it’s important to take your IID agreement seriously and stay compliant with the terms of the program. Common violations include: 

  • Driving any car without an installed interlock device 
  • Failing a rolling retest or having someone else blow into the device for you 
  • Tampering with the device or failing to keep it calibrated 
  • Driving outside approved bounds (typically, work and school) 

If you violate your IID agreement, you can face fines, license suspension, and even jail time. You may also have to wait longer before you can remove your SR-22, which means more time paying higher premiums. 

Make Sure You Have the Right SR-22 Insurance with Your IID

An ignition interlock device is a second chance to get back on the road after a DUI. Don’t waste it! Don’t forget that you also need SR-22 insurance to legally drive while you have an IID. At SR-22 Adviser, we help drivers find the insurance they need at the best possible price. All it takes is a few minutes for a quote for cheap SR-22 insurance from our partner. 

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