What Your Ignition Interlock Failure Reading Means

When you have an ignition interlock device, the last thing you want to do is fail your breath test. Unfortunately, there are a few ways that a test can fail, causing you frustration if you’re in a hurry to get somewhere. Your car may not start, or you are driving and fail a test while the vehicle is in motion, causing more travel delays. Plus, a test failure of any sort is recorded and sent to your reporting agency, which could have more consequences than showing up late for a meeting.

Plenty of people with ignition interlock devices have had failed readings that were easily explained. Maybe you still have some mouthwash residue in your breath. Perhaps the device is malfunctioning or defective. Or, maybe you’ve been drinking.

The odds of your ignition interlock being defective or malfunctioning are slim. At your periodic service appointments, technicians ensure the device is working properly and the data that is recorded includes information about the device itself. Of course, nobody can guarantee each device is working perfectly, all the time. But, with the technology and specifics regulated by the federal government, it is more likely your test failure is due to the presence of alcohol in your breath sample. As the Maryland Motor Vehicle Administration website states: A defective device will not give failed readings.  A failed reading only comes from something on the person’s breath.

If this is the case and you have recently consumed alcohol or used an alcohol-based mouthwash, you will have opportunities to correct your failed test. Since mouthwash and similar products have no effect on your ability to drive, you should be cleared to drive at the next testing prompt. However, if you have been drinking alcohol, even one drink could put you over the limit. If you re-test, you could have enough test failures to put the device into “lockout” mode and you will not be able to drive your car. Plus, your blood alcohol concentration (BAC) reading will be recorded and sent to your agency, which may not be a positive factor in your rehabilitation.

If you have a failed ignition interlock test, make sure that you are not attempting to operate your vehicle after drinking alcohol. Give yourself time to submit a clean sample if you’ve been using mouthwash and if all else fails, call your ignition interlock service provider for further instruction.