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How an ignition interlock device works

Posted at 10:27 AM, May 06, 2019
and last updated 2019-05-06 23:23:25-04

The ignition interlock device, or IID, is designed to keep drunk drivers off the road. The process of getting the device begins with a traffic stop and conviction.

Current Wisconsin law requires all repeat drunk drivers and first-time offenders with a blood alcohol level of 0.15 or higher to install an IID.

Smart Start Wisconsin supplies the devices to companies including Fast Times Automotive in Menomonee Falls.

The device sits on the vehicle's dashboard. When starting, the screen reads "INITIALIZING." When it reads "BLOW," Amy Cry of Smart Start says users have to hum and blow into the mouthpiece.

Blow a 0.02 or higher and the car will not start. Blow under that and drivers can get on their way, but the device begins what's called a rolling retest.

"Rolling retest are the tests that happen after you start the car with the initial blow," Cry said.

The first rolling retest happens within seven to 15 minutes after the car starts.

"One thing people think is that (the car) just stops, like while in the middle of your driving. It doesn't," Cry said.

The IID gives drivers time to pull over to take the test, or they can take it while driving. If they blow over a 0.02 an alarm goes off, the lights start flashing and the horn goes off.

"One thing people think is that (the car) just stops, like while in the middle of your driving. It doesn't." — Amy Cry of Smart Start

It's a built-in safety measure in case the driver got someone else to blow into the device to start the car.

"If you're going to have somebody start the car for you then I always thought, 'Well, why wouldn't you just have that person drive?' " said Cry.

Some states require IIDs come equipped with cameras on them. Wisconsin does not.

"Without these cameras that's kind of a disadvantage of the device is that we don't know who's taking the test," said Cry.

The Wisconsin Department of Transportation reports a little more than half of the people required to install the devices actually do.

Offenders pay at least $85 a month for the IID, and they must have it serviced and recalibrated every 60 days. If they don't, they will be locked out of the car and have to pay a fee to have it unlocked.

State Sen. Alberta Darling and Rep. Jim Ott have introduced a bill that would require all convicted OWI offenders to have an IID in their vehicle.

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