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Many people assume that cold weather can damage an ignition interlock device. But the truth is a little more complicated than that.

Yes, ignition interlock devices sometimes take longer to start-up in cold weather. And, shallow temperatures may cause ignition interlock devices to stop functioning temporarily. However, cold weather won’t directly damage the device.

Below, we explain how extreme temperatures can affect your ignition interlock and what you can do to help it function properly under those conditions.

Tips for Using Ignition Interlock Devices in Cold Weather

Use a High-Quality Battery

All the good intentions in the world won’t keep an ignition interlock device functioning if the battery is sub-par. It’s essential to choose a good battery for your device — and to ensure that it’s always ready to rise to the occasion.

Use the Hang and Tap Method

This helps prevent moisture from entering the internal circuitry of your interlock device. Some recommend hanging the device upside down in your vehicle (with the mouthpiece removed).

When you’re ready to start the car, warm the mouthpiece and gently tap it against your knee. This helps remove any moisture in the mouthpiece before you use the device.

Perform a Warm-Up Cycle

There are two ways to use warm-up cycles to ensure that your ignition interlock is functioning correctly:

  • Start your vehicle at the same time every day, and program a warm-up at that time.
  • Do a manual warm-up cycle — turn your key in the interlock, turn it off, and begin testing after the device has had two minutes to boot up.

Hot Weather and Ignition Interlock Devices

Protecting an ignition interlock device from the heat and sun is very simple.

Fortunately, ignition interlock manufacturers regularly test their devices in extreme temperatures, so your device should start up within a few minutes (regardless of the heat).

  • Shield your device from the sun: Your vehicle gets much hotter if the sun is shining directly on it. Park in the shade or consider using portable shields to keep the sun off your car.
  • Keep your mouthpiece cool: Providing a breath sample over a hot mouthpiece can be decidedly uncomfortable. So, remove the mouthpiece after each use and take it inside your home.
  • Don’t use “tricks” to cool your device down. Beware of internet tips that advise wrapping your ignition interlock in a wet cloth or pouring cool liquids down the air tubes.

RoadGuard Interlock Devices and Extreme Temperatures

In extreme heat, RoadGuard Interlock LLC (DUI) devices may need additional time to cool down before use.

Some states allow for the removal of handsets from their helix cables. This way, you can take the device inside your home. This can help minimize waiting times in scorching weather.

In cold weather, device warmup times may increase by two minutes or more. Taking the device inside can help shorten warmup times, but you should never disconnect the handset while the device is on.

Wait for the device to be fully powered down before disconnecting, and be sure to connect the handset to the helix cable before turning the unit on. This will reduce the potentiality of false violations.

Ignition Interlock Devices from RoadGuard Interlock

While other ignition interlock devices can take up to three minutes to function correctly, DUI’s devices typically give results in under 10 seconds.

Our interlock devices are also specially designed to operate accurately in temperatures ranging from -40F to 185F. Once your seatbelt is fastened, you’re ready to go — no matter the weather!

In some cases, you’ll be allowed to disconnect your ignition interlock device. This is rare but is sometimes permitted to prevent the device from sitting in your car during extreme weather conditions. Be sure to obtain formal permission before disconnecting your device.

For more information about how the weather can affect your ignition interlock device, check our Dräger Interlock 7000 user device manual.

If you have questions about our ignition interlock devices (or how they function in extreme temperatures), our team is prepared to help. Reach out to the experts at RoadGuard Interlock today to find out more.

*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 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.