Starting a Vehicle With an Ignition Interlock In Cold Weather — 7 Tips That Really Work

Cold weather can't stop you from driving with an ignition interlockThis winter has been insanely cold. Some regions of the country have faced temperatures of 10 to 20 below zero – and that’s not taking wind chill into account. Drivers who use ignition interlocks are experiencing difficulties in these extreme conditions. And little wonder – the precision circuitry that detects alcohol on one’s breath is subject to problems when placed in a freezing environment.

Fortunately, there are ways to get around the difficulties. But while much of the country is in a deep-freeze you will need to take precautions so that you can always start a vehicle with an ignition interlock in cold weather.

Baby, it's cold outside, but you can start your ignition interlock if you follow some sensible adviceThe temperature isn’t the real problem – moisture is. When you breathe into an interlock, the moisture from your breath collects inside the device. Under normal conditions this is fine, but when the vehicle is left in extremely cold conditions the moisture can freeze onto the device’s delicate circuitry, causing temporary problems.

The good news is there are ways to make sure that dropping mercury doesn’t keep you from taking to the road. Here’s how to start a vehicle with an ignition interlock in cold weather – every time:

  1. Have a good battery. This is huge. If you’re in any cold weather state, having a battery over four years old is living on borrowed time whether or not you have an ignition interlock. Check out your alternator too – unless these two elements of your electrical system are in top shape, you can stop reading now and buy a bus pass.
  2. Bring the device inside if possible. If your state allows you to disconnect your ignition interlock, then bring it inside when you park. This keeps the device warm and ready to go.
  3. Hang it upside down. If you can’t detach the device due to state regulations, then hang it upside down on the steering wheel with mouthpiece removed. The moisture will collect and freeze down at the top of the device, away from the circuitry.
  4. Tap the device GENTLY. After you warm the device, tap it downwards GENTLY a couple of times on your knee, to force out any moisture that’s in the mouthpiece. Did we mention GENTLY?
  5. Program a warm-up. In many states you can ask for your device to be programmed to turn on at a set time every day. If you leave for work or school at a regular time, you can have your device warmed up and ready for you.
  6. Do a manual warm-up cycle. This is easy, and should work every time. Turn your key on, and let your device wake up. Immediately, turn the key off again. You’ll see the “Wait” light, and then it will ask for a test. DON’T BLOW. Let it go back to sleep for 2 minutes. Then turn the key again, and take the test when it tells you to. You’ll be good to go.
  7. Drive your vehicle regularly. That means 2-3 times a week if you’re being bombarded by cold weather. This makes good sense whether or not you have an interlock. Driving your car charges the battery, which is ultimately what keeps the interlock and your car working.

If you live in a cold climate, taking proper precautions with your ignition interlock will become a habit. There’s no reason that you can’t be driving, legally and safely, no matter how cold it is outside.