Suspensions & Hearings

In order for an IID to be installed, your vehicle must have a 12-Volt electrical system and it must be in good working order. Operators are encouraged to check with the approved IID vendor/service provider for more details. The IID will not be installed on motorcycles.


Once the IID is installed in your vehicle, you will receive instructions from your service provider on how to operate the device.

Follow the steps below:

  • Step 1 - Turn on the vehicle's ignition and wait for the IID to display instructions indicating you need to take an initial breath-alcohol test.
  • Step 2 - Blow into the IID until you have provided an acceptable breath-alcohol test sample. If you pass the initial breath-alcohol test, the IID will allow you to start your vehicle.

If you fail the initial breath-alcohol test (Blood Alcohol Concentration "BAC" greater than .02%), you will not be able to start your vehicle. You will need to wait for your BAC to decrease before you take another breath-alcohol test.

If you fail a second time within a service period, your vehicle will go into lockout and you will need to visit your service provider within 48 hours to continue operation of the vehicle. A service period is the 1-30 day period following the last IID calibration or service visit.

  • Step 3 - After the vehicle has started, you will be required to take rolling re-tests at random intervals while operating the vehicle. When it is time to take a rolling re-test, the IID will beep, alerting the operator that they have five minutes to take the breath-alcohol re-test.
  • Step 4 - You may take the rolling re-tests while driving, but it is recommended that, if it is safe to do so, you pull your vehicle over to the side of the road and take the breath-alcohol re-tests. If you do not take the rolling re-test, or if you turn the ignition off before taking the rolling re-test, this will be considered a missed test.

Please Note: The IID will never shut your engine off after it has been started.

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