Ignition Interlock Winter Tips: Prep Your Vehicle Battery for Cold Weather

Interlock not working in the cold? Winter weather may cause your ignition interlock device (IID) and vehicle to act up. Follow our ignition interlock winter tips to keep your IID and vehicle running smoothly this season.

Snow. Salt. Ice. Winter weather can be tough on your vehicle. Freezing temperatures may be even more challenging to deal with if you have an ignition interlock device (IID) requirement following a DUI conviction.   

Fortunately, with a few practical ignition interlock winter tips and the support of the experienced Intoxalock® team, you can keep your IID operating smoothly all season. Here are some simple steps to help you manage any potential cold-weather interlock issues. 

This blog isn't legal advice. For specific questions, consult a qualified DUI attorney. If you have immediate questions about ignition interlocks, call us 24/7 at (888) 283-5899.  

The Relationship Between Your IID and Your Vehicle Battery  

Worried your interlock device won't turn on in cold weather? It's a valid concern. The American Automobile Association (AAA) warns that car battery maintenance is key to reliably starting your car over winter. This is important to know if you use an ignition interlock device.  

Your IID prevents your vehicle from starting if it detects alcohol in your breath. The interlock draws a tiny amount of power from your car's battery and it will drain your battery to some degree, but this won't be a problem if your vehicle is in good working order and driven regularly. 

How Do Cold Temperatures Affect Vehicle Batteries? 

Cold weather slows down chemical reactions in car batteries, lowering their ability to store and deliver power. Most ignition interlocks draw an immeasurably small amount of energy even when the vehicle is off, so a weak or aging battery can quickly become a problem in freezing weather. However, most interlocks, including Intoxalock’s, have a sleep mode to further reduce battery draw when the vehicle isn't in use. 

Why Do Low Temperatures Slow Down Ignition Interlock Startup? 

An IID contains temperature-sensitive sensors and electronic warming components that get the device into the correct operating temperature range. In cold conditions, these parts take longer to reach the proper operating temperature, delaying the startup process. In mild cold (between 60F – 32F), you might only wait between 60 – 80 seconds, but the delay may be slightly longer in freezing temperatures (31F or lower). 

Tip: Warm up your interlock device by starting your car a few minutes earlier on cold mornings. This may help prevent common IID problems and unnecessary delays. 

What Happens If a Battery Dies with an Interlock Device?  

If a battery dies with an interlock device, your car won't start. Vehicle batteries in frigid climates typically last three to five years. Older batteries are more likely to have issues or fail during winter. Following our ignition interlock winter tips can help, but if you're unsure about your battery, have it tested at one of Intoxalock's more than 5,500 service centers nationwide.  

Tip: If you want to schedule a quick winter readiness check on your IID but aren't sure where to start, call (888) 283-5899 to speak with one of our experienced State Specialists. They can connect you with the right local service center for your needs. 

What Are the Basic Steps to Protecting Your Battery for Winter IID Use? 

Strong battery performance is one of the most vital factors in preventing cold-weather interlock issues.   

1. Stay on Top of Battery Health 

Replace it before the season changes, especially if your battery is approaching the three- to five-year mark. Corrosion on battery terminals can interfere with the power flow to your IID, so keeping them clean helps maintain consistent performance.  

Tip: Intoxalock makes it easy to stay ahead of battery problems. To confirm everything is in top shape or for more battery-related ignition interlock winter tips, schedule a pre-winter inspection at one of our 5,500+ service centers. Call (888) 283-5899 to find a location near you.  

2. Disconnect Your Handheld 

Check if you’re allowed to disconnect your device to bring it inside. In many states, you can disconnect your device to keep it warm indoors, which helps it work faster in cold weather and preserves battery life. However, if disconnecting your device isn’t permitted in your state, it could be considered a tampering violation. If you’re unsure, check the user manual you received at your installation appointment or ask an Intoxalock representative to avoid any issues. 

3. Use Sleep Mode or Battery-Saving Features 

If you know you won't be driving for a few days, putting your interlock in sleep mode can protect your car battery. It reduces your IID's drawing power while maintaining compliance with monitoring requirements. This may prevent your interlock device from draining your battery during cold spells or when you park the car for days at a time.  

Tip: All Intoxalock devices include sleep mode. Our State Specialists are available 24/7 to help you activate it without risking compliance issues. 

4. Consider Trickle Chargers and Block Heaters 

Using a trickle charger, block heater, or other winter add-ons can help prevent dead batteries, device freezing, and other interlock issues.  

• Trickle chargers for interlocks are an electrical device that provide a steady, low-amp current to help maintain battery life and prevent dead batteries, while protecting against overcharging.  

• Block heaters use an electrical heating element to warm your car battery and fluids before starting the engine. 

Other Accessories and Services 

Yes. When using the winter accessories mentioned below, make sure they are approved for vehicles with ignition interlock devices to avoid damage or compliance issues. Contacting a State Specialist at (888) 283-5899 is the easiest way to get guidance and ignition interlock winter tips tailored to your state's requirements and climate. 

Carry Backup Gear Like Portable Jump Starters 

Car battery failures are common in winter. Compact portable jump starters are user-friendly and can get you back on the road quickly, without needing another vehicle or driver.  

Service Support from Local Intoxalock Centers 

With over 5,500 service centers nationwide, Intoxalock makes it easy to get ignition interlock winter tips when needed. Ninety percent of our customers live within 15 miles of a location, many of which offer same-day appointments and winter checkups to keep your device compliant and working well. 

More Resources for Winter IID Advice 

Don't let frigid weather catch you in the cold. Following proper car breathalyzer cold-weather tips can keep your car battery strong and prevent winter weather interlock issues.  

For expert ignition interlock winter tips, troubleshooting help, or guidance on winter-ready accessories, call a State Specialist at (888) 283-5899. We're here 24/7 to point you in the right direction for battery checks, sleep mode setup, and recommend winter accessories based on your state's requirements. 

Prefer online help? Chat with a State Specialist anytime at Intoxalock.com. 

Want to learn more? Intoxalock's Cold Weather Protection Guide provides additional ignition interlock winter tips.