What a Smart Start interlock device does
A Smart Start interlock device is an alcohol-detection system installed in your vehicle's ignition. Before the engine will start, you blow into the device; if it detects alcohol on your breath above a set threshold, the engine will not turn over. The device records every test result and sends that data to Smart Start's monitoring centre, which reports to the court or licensing authority that ordered the installation.
You are required to install one when a court orders it as a condition of keeping your driving privileges after a DUI or DWI conviction. Some states allow interlock as an alternative to a full license suspension; others require it alongside a suspension period. The device does not remove the conviction from your record—it is a monitoring tool that lets you drive under strict conditions while proving you are not driving impaired.
Smart Start is one company among several that manufacture and monitor these devices. Your state's court or Department of Motor Vehicles will either assign you to Smart Start or give you a choice of approved vendors. The cost, installation location, and monitoring requirements vary by state and by the terms of your sentence.
Key Takeaways
- A Smart Start interlock requires you to blow into a device before starting your car; if alcohol is detected, the engine will not start.
- Installation is ordered by a court as a condition of your sentence, not something you choose voluntarily unless your state offers it as an alternative to suspension.
- You pay for installation, monthly monitoring, and calibration checks; costs range widely by state and service plan, typically several hundred dollars per month.
- The device records all test results and sends them to Smart Start's monitoring centre, which reports to the court or DMV on your compliance.
- Tampering with, bypassing, or failing a rolling retest (a test while driving) can result in vehicle lockout, license suspension, and additional criminal charges.
How the device works day to day
When you get in your car, you insert your key or press the start button as normal. The interlock device will display a prompt asking you to provide a breath sample. You blow steadily into the mouthpiece for several seconds. The device analyzes your breath alcohol content (BAC) and either allows the engine to start or locks it out.
If your BAC is below the threshold set by your state (usually 0.02 to 0.04 percent), the engine starts and you can drive. If your BAC is at or above that threshold, the device will not allow ignition. You must wait a set time—typically 5 to 15 minutes—before you can try again. Repeated failed attempts are logged and reported to Smart Start's monitoring centre.
While you are driving, the device will prompt you to take a rolling retest at random intervals. This is a breath test you perform while the vehicle is in motion. You have a set time (usually 5 to 10 minutes) to pull over safely and provide the sample. If you fail a rolling retest or do not provide a sample in time, the device will log a violation. Depending on your state's rules, this may trigger a vehicle lockout, a warning letter, or a report to the court.
Every 30 days, you must bring your vehicle to a Smart Start service location for a calibration check. A technician downloads the device's data, verifies it is working correctly, and resets the test counter. This appointment is mandatory; missing it is treated as non-compliance and reported to the court.
Installation and initial setup
Your court order will specify which vendor you must use or whether you have a choice. If Smart Start is assigned to you, contact their customer service line to schedule an installation appointment. You will need to provide your vehicle's make, model, and year, your driver's license number, and your court case number or sentencing document.
Installation typically takes 1 to 2 hours. A Smart Start technician will install the device on your vehicle's dashboard or steering column, connect it to the ignition system, and test it to confirm it is working. You will be shown how to use it and given written instructions. The technician will also explain the rolling retest process, the calibration schedule, and the consequences of non-compliance.
You will be assigned a Personal Identification Number (PIN) that you must enter before each breath test. This PIN prevents someone else from blowing into the device on your behalf. You are responsible for remembering your PIN; if you forget it, you cannot start your vehicle and must contact Smart Start to reset it.
Installation costs vary by state but typically range from $100 to $300. Monthly monitoring and calibration fees usually run $50 to $100 per month, though some states subsidize costs for low-income drivers. You are responsible for all costs unless your state's program covers them.
Compliance requirements and reporting
Smart Start monitors your device data continuously. Every test result—passed, failed, or missed—is recorded with a timestamp and sent to Smart Start's servers. The company generates compliance reports that are sent to the court or DMV on a schedule set by your sentencing order, usually monthly or quarterly.
Your compliance record includes the number of failed breath tests, rolling retest violations, missed calibration appointments, and any attempts to tamper with or disable the device. A single failed test does not automatically trigger a violation; most courts allow a small number of failures before taking action. However, a pattern of failures, a missed calibration, or a rolling retest violation will be reported and may result in a court hearing, extended interlock requirements, or license suspension.
You must keep your vehicle in working order and maintain the interlock device. If your vehicle breaks down or the device malfunctions, contact Smart Start when ready. Driving without a functioning interlock when one is court-ordered is a violation. If the device fails, Smart Start will arrange a replacement or repair at no additional cost if it is a manufacturer defect.
Your interlock requirement will end on the date specified in your court order. This date is based on your conviction, your sentence, and your state's mandatory minimum interlock period. Before that date, you cannot remove the device; doing so is a criminal offense. When the date arrives, you must schedule a removal appointment with Smart Start. The technician will uninstall the device, read the final data report, and provide you with a removal certificate to show your DMV or court.
What happens if you fail or tamper with the device
A failed breath test means your BAC was at or above the threshold. One or two failures over several months may not trigger when ready action, depending on your state's rules. However, a pattern of failures—typically three or more in a rolling 30-day period—will be reported to the court. The court may order you to attend an alcohol education program, increase your interlock period, or suspend your license.
A rolling retest violation occurs when you fail a test while driving or do not provide a sample within the allowed time. This is treated more seriously than a startup test failure because it suggests you are driving while impaired. A single rolling retest violation is usually reported to the court and may result in a warning or a license suspension.
Tampering includes attempting to bypass the device, disconnecting it, using a different vehicle without an interlock, or allowing someone else to blow into it for you. Smart Start's device includes anti-tampering sensors that detect disconnection, power loss, or physical damage. Any tampering attempt is logged and reported when ready to the court. Tampering is a separate criminal offense in most states and can result in arrest, additional fines, and an extended interlock requirement.
If you miss a calibration appointment, Smart Start will send you a warning notice. If you miss a second appointment, the violation is reported to the court. Repeated missed appointments may result in license suspension or an extension of your interlock period.
Cost breakdown and payment options
The total cost of an interlock device includes several components: installation, monthly monitoring, calibration checks, and removal. Installation is a one-time fee, usually $100 to $300. Monthly monitoring and calibration combined typically cost $50 to $100 per month, though this varies significantly by state and by Smart Start's service plan in your area.
If your interlock requirement lasts one year, you can expect to pay roughly $700 to $1,500 total, not including the initial installation. If your requirement is longer, costs accumulate accordingly. Some states offer reduced fees for low-income drivers or allow payment plans; contact your local Smart Start office or your court to ask whether you are may be able to access.
You are responsible for paying these fees. If you do not pay, Smart Start will report non-payment to the court, and your license may be suspended. Some courts allow you to request a fee waiver or reduction based on financial hardship, but you must file a formal request with the court, not with Smart Start.
State variations in interlock requirements
Interlock laws differ by state in several important ways. Some states require interlock for all DUI convictions; others only for repeat offenders or high BAC readings. Some states allow interlock as an alternative to a full license suspension; others require it in addition to a suspension period. The mandatory minimum interlock period ranges from 6 months to 3 years depending on your state and the severity of your conviction.
The BAC threshold for the device also varies. Most states set it at 0.02 percent (lower than the legal driving limit of 0.08 percent), but some use 0.04 percent. A few states allow you to request a lower threshold as part of your compliance effort.
Your state's DMV or court website will specify the interlock requirements for your conviction. If you are unsure, contact the court that sentenced you or your state's DMV directly. Do not rely on Smart Start alone for this information; the court order is the binding document.
Frequently Asked Questions
Can I remove the interlock device myself?
No. Removing the device yourself is a criminal offense and will result in arrest and additional charges. You must wait until your court-ordered interlock period ends, then schedule a removal appointment with Smart Start. The technician will uninstall it and provide a removal certificate.
What if I need to drive someone else's car while my interlock is active?
You cannot drive a vehicle without an interlock if one is court-ordered for you. Doing so is a violation and will be reported if discovered. Some states allow you to request a temporary exemption for specific vehicles (such as a work vehicle or a family member's car), but you must file this request with the court in advance and it is rarely granted.
Can I pass a breath test if I have eaten or drunk something non-alcoholic?
Mouthwash, some cough syrups, and fermented foods can contain small amounts of alcohol and may trigger a failed test. If you fail a test and believe it was caused by a non-alcoholic product, contact Smart Start when ready and explain what you consumed. Document the product (keep the bottle or packaging) and provide it to Smart Start. A pattern of failures from the same cause can be presented to the court as evidence of a false positive.
What happens if my car breaks down while I have an interlock?
Contact Smart Start when ready and explain the situation. If your vehicle is in the shop, you cannot drive it, so the interlock is not a concern during that time. If you need to drive a rental car or borrow a vehicle, you must inform Smart Start and the court. In most cases, you are not allowed to drive a different vehicle; however, some courts will grant a temporary exemption if you can show the original vehicle is being repaired.
Can I travel out of state with an interlock device?
You can travel, but your interlock device must remain installed and functional. If you will be away for more than a few days, contact Smart Start to arrange a calibration appointment in the state you are visiting or to extend your appointment schedule. Some states have reciprocal agreements with Smart Start; others do not. Check with Smart Start and your court before traveling to confirm what is required.