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RoadGuard Interlock devices help protect drivers by preventing alcohol-impaired driving and are easy to use. If issues with the device’s usage do arise, our ignition interlock devices display easy-to-read messages to help you provide a correct breath sample so that you can get back on the road quickly. If you are experiencing ignition interlock device problems, the easiest way to resolve malfunctions is to understand how to use your device properly and what to do in case you experience any device issues.

For information about how to use and store your ignition interlock to avoid malfunctions, check out 6 Ways You Can Avoid Ignition Interlock Malfunction. However, if your device does show an error, don’t worry.  Error messages on RoadGuard Interlock devices are self-explanatory and simple to troubleshoot.

Breath Test Messages

If you’re experiencing issues passing the breath test on your interlock device, or you see a flashing red light or hear a beep, check the display. It should provide a simple and clear message to help you troubleshoot. Here are some of the most common ignition interlock device problems:

Blow Longer! Repeat Test

This error means your breath sample didn’t last long enough. Press the OK button and wait a moment while the interlock resets. After a brief wait, blow slowly into the mouthpiece until you hear the tone stop, ensuring the blow lasts long enough for the device to obtain a complete sample.

Blow Stronger! Repeat Test:

Similar to the previous error, this means the breath sample you provided didn’t have enough force. Press the OK button and wait again, then blow into the mouthpiece with more force. Continue until the tone stops, blowing enough for the system to read the sample.

Suck After Blow Repeat Test:

For the ignition interlock to successfully analyze your sample and clear you to drive, it needs to test the sample in both directions. Retake the test and wait for the tone to stop, do not remove your mouth from the mouthpiece, and then sharply suck air back in through the device. Continue until you hear a beep.

Interferent Detected:

This ignition interlock malfunction occurs when the IID detects low air quality, and it’s unable to analyze the sample successfully. The easiest way to resolve this error is to rinse your mouth with water and open the windows of the vehicle to ensure the air it’s detecting is clean. While you’re doing this, press OK on the IID, and it will begin a countdown. After the countdown finishes, test again.

Random Retest:

Due to state requirements, the ignition interlock is set to request a retest at random intervals following your initial test. The device will beep with a continuous tone. Press the OK button and test again. If the test fails, your vehicle may begin honking and flashing lights, if required by your jurisdiction. You can disable this by turning the car off. If the device has an active countdown, you’ll need to wait for it to finish to test again.  Remember, DUI strongly recommends that you pull over to a safe location to perform any retests.

Service Lockout:

The ignition interlock device must be serviced within specified periods on an ongoing basis (typically every 30 to 60 days, depending on your state’s requirements). If the device is not taken to a service location within the required period, it will lock you out and display “Service Lockout.” The device will display a several-day service countdown before you are locked out. When this happens, call your technician or service center for assistance. A lockout can be frustrating, and it’s critical to ensure you handle it according to your state requirements. For more information about these situations, check out What to Do in Case of an Interlock Device Lockout and other helpful web pages in the RoadGuard Interlock support center.

Ignition Interlock Malfunction: Driving with an Ignition Interlock Device

RoadGuard Interlock will help you navigate through your ignition interlock device requirements and get back on the road after a DUI and get back to full driving freedom faster. Working through ignition interlock device problems can occasionally be frustrating, but the RoadGuard Interlock devices make it simple to solve these problems when they occur. DUI is dedicated to helping you get back behind the wheel safely. If you are experiencing ignition interlock problems, please feel free to contact us with any questions.

*Links to any third-party websites herein are provided for your reference and convenience only. RoadGuard Interlock did not create nor develop and does not own any such third-party websites. RoadGuard Interlock does not endorse nor support the content of, nor any opinions stated in any such third-party website links. RoadGuard Interlock is not responsible for the content of any third-party website or its accuracy or reliability. Nothing contained in this article or in any such third-party website shall be considered legal advice or be deemed to constitute legal advice. For any legal advice concerning a DUI arrest, charge, conviction, or consequences thereof, you should contact an attorney of your choice.