Ignition Interlock Devices (IID): What You Need to Know

Ignition Interlock Devices (IID): What You Need to Know

An Ignition Interlock Device (IID) is a court-ordered breath-testing device installed in a vehicle to prevent drivers from operating it while under the influence of alcohol. IIDs are commonly required after DUI-related arrests or convictions, and their use has become increasingly widespread across California and the U.S.

Understanding how ignition interlock devices work—and how they affect driving privileges—is critical for anyone facing DUI charges.

What Is an Ignition Interlock Device?

An ignition interlock device is connected to a vehicle’s ignition system. Before the car can start, the driver must blow into the device. If alcohol is detected above a preset limit, the vehicle will not start.

Many devices also require random rolling retests while driving to ensure the driver remains sober throughout the trip.

When Is an IID Required?

In California, ignition interlock devices may be required in cases involving:

• First-time DUI convictions
• Repeat DUI offenses
• DUI with injury
• High BAC levels
• Underage DUI
• DUI with a minor passenger

Courts or the DMV may require IID installation as a condition of:

• License reinstatement
• Probation
• Restricted driving privileges

How Long Do You Have to Use an IID?

The length of IID requirements depends on the offense:

• First DUI: Up to 6 months
• Second DUI: 12 months
• Third DUI: 24 months
• DUI with injury: Up to 30 months or longer

Failure to comply can result in extended suspension periods or additional penalties.

Costs Associated With Ignition Interlock Devices

Drivers are responsible for all IID-related costs, including:

• Installation fees
• Monthly monitoring fees
• Calibration and maintenance costs

On average, costs range from $70–$150 to install, plus $60–$100 per month. Some low-income drivers may qualify for financial assistance programs.

What Happens If You Violate IID Rules?

Violating IID requirements can have serious consequences, such as:

• Extended IID usage period
• Probation violations
• License re-suspension
• Additional fines or penalties

Common violations include:

• Failing a breath test
• Skipping required calibrations
• Allowing another person to blow into the device

How IID Requirements Affect Bail and Release

In some DUI cases, IID installation may be required as a condition of release or probation after bail is posted. Courts may also impose additional conditions such as alcohol monitoring or restricted driving.

Working with a bail bond agency ensures you understand all release requirements and remain compliant to avoid re-arrest.

Need Help After a DUI Arrest?

A DUI arrest can come with confusing conditions—bail requirements, IID installation, court dates, and DMV rules. Our experienced bail agents help clients navigate every step of the process, from posting bail to understanding court-ordered conditions like ignition interlock devices.

We’re available 24/7 to answer questions and help you or your loved one secure release quickly and responsibly.

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