Wisconsin Ignition Interlock 2025 Guide
If you’ve recently been charged with an OWI or DUI in Wisconsin, you’ve probably heard the words ignition interlock device (IID) mentioned in court. It can feel overwhelming, but don’t panic.
This guide will break it all down, including:
• Who needs a Wisconsin IID
• How they work
• How to get one installed
• How long you’ll need it
• Tips to stay compliant
By the end, you’ll know exactly what to do to get back on the road legally.
What is an Ignition Interlock Device?
Purpose: Stops your car from starting if your blood alcohol concentration (BAC) is over the compliance limit, usually 0.02% or lower.
How it works:
- Blow into the device before starting your car.
- If your BAC is below the limit, the car starts.
- If it’s above the limit, the ignition stays locked.
IID Myths vs. Facts
There are a lot of rumors out there about ignition interlocks. Let’s clear up the most common ones:
Myth: Ignition interlocks will drain my car battery.
Fact: Smart Start devices draw very little power. No more power than your car’s clock or radio preset memory.
Myth: The IID can shut my car off while I’m driving.
Fact: Your safety always comes first. Smart Start devices never turn off a running vehicle. If a retest is missed or failed, the device simply records the event for review.
Myth: Anyone can blow into the device for me.
Fact: Our devices have built-in cameras to verify it is the driver taking the test, preventing tampering or misuse.
Myth: I’ll be stuck at the roadside if I fail a rolling retest.
Fact: If alcohol is detected, the device logs the violation but does not stop your vehicle. You’ll be able to drive to a safe location.



