FAQs & Myths:


Having an interlock installed on your vehicle is not an everyday occurrence. We understand that you may have several questions regarding how the device works. Here are answers to some common questions.


What is an ignition interlock?


An ignition interlock is a breath analyzer wired into a vehicle’s starting system that prevents the vehicle from starting if the driver has had too much to drink. Ignition interlocks are about the size of a cellular phone and are attached to the vehicle with a curly cord that disappears under the vehicle’s dash.


What does an ignition interlock cost?


An ignition interlock will cost around $2 per day ($65–75 per month) to lease. Some ignition interlock companies will charge up to $65 to install and $25 to remove your ignition interlock. With Affordable Ignition Interlock, we only charge $27.50 for installation and $22.50 for removal.


How accurate is an interlock?


All interlock devices must be certified to meet NTHSA specifications for accuracy and dependability and often by each state’s specs as well. Almost all interlock devices are accurate within .005.


Can the interlock unit drain my battery?


The LifeSafer FC100, used by Affordable Ignition Interlock, uses minimum battery power. Problems occur only if there is already an electrical problem with your car or if the car’s battery has died.


Will eating spicy foods cause my interlock to fail?


The mix of spicy foods and HCL from your stomach creates methane, which in older interlock models would register as a false positive. With the new alcohol specific technology used in the Affordable Ignition Interlock device, this phenomenon does not occur anymore.


Can cigarette smoke and snuff cause my interlock to fail?


You should always take a few deep breaths before attempting a test, if you are a smoker. While cigarette smoke does not affect the interlock, however; you should never blow smoke into any unit.


Will filling my car with gasoline at the service station cause my interlock to fail?


Refilling your car at the gas station will not create a false positive test. In fact, gasoline in high concentration will not register as a fail on an alcohol specific interlock.


Will I fail if I use perfume, hairspray, after-shave, or colognes?


Yes. These items all contain large amounts of alcohol, and all interlock devices will detect this alcohol if it is present in the sample given.


Can using mouthwash cause my interlock to fail?


Some mouthwash brands and sprays have up to 30% alcohol, which will definitely create a positive test on your interlock. We recommend that you switch to a nonalcoholic mouthwash while fulfilling your temporary license restriction period. However, alcohol levels from mouthwash or sprays should start to drop within 15 minutes, and washing your mouth out with water will help it drop faster. We recommend that everyone rinse his or her mouth with water before every test.


If I eat chocolate mints, Altoids, or chew Dentyne or other gum, will my interlock fail?


Alcohol filled chocolates will register a fail; however, the alcohol in the chocolate will begin to decline in three minutes. Other gums and chocolates with no alcohol in them will not create a false positive test.


Will my interlock fail after I eat cinnamon rolls and donuts?


The sugar and the active yeast in some bread products can combine to create a low-level alcohol fail. However, the same steps can be applied that we recommended for mouthwash users. Simply rinse your mouth with water, before the test, to eliminate the remaining food.


What happens if someone else was driving my car and they blew a fail because they had been drinking?


As the defendant, you are informed that you are responsible for all tests recorded on the vehicle’s interlock, whether you were driving at the time or not. All tests are your responsibility.


Will the interlock shut down my engine or stop my car?


The interlock system will not shut down your car if a breath test is not passed. It is designed to prevent the car from starting without a passing breath test. If you record a positive test while driving, the device records a violation but will not stop your car.


Can I start my car if I only had one beer, glass of wine, or one cocktail?


There are many factors that affect how fast someone metabolizes alcohol, including the size and gender of the person, the average person metabolizes one ounce of alcohol per hour. This means that if the average person has a single drink an hour or more before startup, they should pass the test. The important thing to remember is that everyone metabolizes alcohol at different rates. We do not recommend drinking alcohol at all, if you plan on driving.


Can I start my vehicle without taking a test?


No. The point of the interlock is to make sure you have passed a test before you can start your vehicle.


Is there a safe way for me to do the rolling retest?


While it is easy to do a rolling retest while still driving, many people do not feel comfortable doing so. If you are not comfortable taking the rolling retest while driving, find a spot to pull over so you can take the test. The device automatically gives you three minutes to respond, which is more than enough time to find a safe place to pull over and take the test.


What should be done if we only have one car in our family and have multiple drivers?


Driving a car with the interlock system is not restricted to you, but all drivers must be able to make the hum tone and pass the test. It is also important to remember that you are responsible for all readings registered by the interlock, whether you were driving or not.


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