What Will Set Off an Interlock?

If you’re been convicted of a DUI/DWI, depending on your state, you may be automatically required to get an ignition interlock device installed in your vehicle as part of getting your full driving privileges back. All 50 states and the District of Columbia have ignition interlock laws that spell out who has to get an interlock installed, and for how long. One of the most frequent questions we get from customers is “What will set off an interlock?”

And by set off, we mean two things: What will cause the interlock to lock you out, and what may cause the interlock to cause your lights to flash and your horn to start honking. And remember, the interlock device records everything, and ALCOLOCK must report all data to your monitoring agency.

Ignition Interlock Test Failure

While state laws may vary regarding who has to get an ignition interlock device installed, they all require interlock devices to meet or exceed the National Highway Transportation Safety Administration model specifications for ignition interlock devices. These model specifications require the devices to be very precise, and continually accurate in detecting small levels of alcohol on your breath. All states consider it to be an ignition interlock test failure if your blood alcohol content (BAC) is .02 or .025. Your state paperwork will tell you what the level is in your state. Most people can register that BAC after just one drink.

Startup Test

The startup test is of course, when you first try to start the car to go to work, school, medical appointment, etc. You must give a valid breath sample each time you wish to start the car. If the device does not detect a BAC at or above your state’s set limit, you pass the test, and can start the car. If the device detects a BAC at or above the level, it will sound an alert, and lock you out. You can generally try to give another breath sample in a few minutes. If you have a low level BAC below .02, the device will record that and give you a warning alert, but you can still start the car.

If you fail several startup tests in a row, the device may enter permanent lockout, depending on your state.

Rolling Retest

A rolling retest, or running retest, is when the device prompts you to give a breath sample after you have already started driving. This is to ensure you didn’t start drinking after you started the car. Rolling retests are random, but you can expect several during a one hour period. If you blow a clean sample, you keep driving. If the device detects a BAC at or above your state’s limit, it will NOT SHUT OFF YOUR ENGINE. This, of course, is for safety reasons. However, many states require interlock devices to cause your lights to start flashing and your horn to start honking. It’s important that you pull over and turn off the ignition after failing a rolling retest.

As with a startup test, you will have a chance to give another breath sample in a few minutes.

Accidental Test Failure

So let’s say you haven’t had any alcohol to drink, but the device still registers a BAC high enough to count as a test failure. While it doesn’t happen often, it’s possible. There is enough alcohol in some energy drinks, food, and medications to cause a test failure. This is why we recommend waiting 20 minutes after eating or drinking to submit a breath sample. It is also a good idea to rinse your mouth out with water before giving a breath sample.

If you feel you failed a test because of something other than an alcoholic drink, you should let your DUI lawyer and your monitoring agency know right away. You can also let your service technician know. Make note of the day and time of the test failure.

Attempting to Tamper With or Circumvent the Interlock Device

Ignition interlock devices are equipped with many features to prevent you from tampering with or successfully circumventing the device. These may include a camera, which snaps a picture of you when we calibrate the device. The device stores that picture to compare to the picture it snaps each time you take the breath test. If you have someone else attempt to submit a breath sample for you, the device will register a test failure, and the circumvention attempt.

Devices also recognize your rate of breath flow, and may also require you to hum while giving a sample. They will detect if someone else gives the breath sample. Devices may also set off an alert if you attempt to disconnect it, and enter permanent lockout.

Trust us. Don’t attempt to tamper with or circumvent the interlock device. These are both major program violations that could get you kicked out of the program. Not only that, but you would also face fines and possibly jail time.

Missing a Required Service Visit

Depending on your state, you are required to bring your vehicle into a service center every 30 to 60 days. This is when the technician recalibrates the device as needed, checks to make sure everything is working properly, and transmits all of the information the device has recorded in the most recent service period. That information is transmitted to your monitoring agency. Your device will remind you several days before your scheduled service visit. If you need to reschedule, you should call right away.

You generally have 7 days after a scheduled visit to get into the service center. After a missed appointment, your device will enter countdown mode. If within those 7 days, you do not bring your vehicle into the service center, the device will enter permanent lockout. You may then have to have your car towed to the service center for the technician to reset the device.

Temporary Vs. Permanent Lockout

Temporary lockout is when you fail a startup or rolling retest, but you get to try again in a few minutes. Permanent lockout is when you have failed a specified number of tests in a row, you tried to tamper with the device, or you skipped a service visit. With a permanent lockout, you cannot try again in a few minutes. Only your technician can unlock/reset the device.

As you can see, there are a number of things that will set off an interlock — some more seriously than others. But by abiding by the program rules, you can avoid setting it off. Full compliance with the rules will have you finishing up your restricted driving program in the shortest amount of time possible.

Schedule Your Ignition Interlock Device Installation

If you need to get an IID installed, ALCOLOCK is ready to help. We have ignition interlock device installation locations all across the country. To schedule your interlock device installation, just call the service location most convenient to your work or home. Remember that where you get the installation done is where you will go for your service appointments. You can also call ALCOLOCK directly at (866) 700-9300. In most states, you must have the installation completed within 30 days of getting your restricted license.

Because you will need someone to drive you and your vehicle to the appointment, you will want to coordinate with your ride before you pick a day and time for installation. If someone else will be driving the vehicle while you have the IID installed, they should come with you.

Installation appointments usually last about an hour. First, the technician will physically install the device in your car. Then they will calibrate the device and train you and anyone else how to use it. The service technician will explain what all of the lights, sounds, and messages mean, and give you a user’s manual to help you if you forget anything. Finally, you will set up your first service visit. Those are usually every 30 days and last about 20 minutes.

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