Ignition Interlock Devices (IIDs)

What is an Ignition Interlock Device?

An ignition interlock device (IID) is a device that is wired into a vehicle's ignition system. After an IID is installed into a vehicle, it requires the driver to provide a breath sample in order for the driver to start the engine . If the device detects any alcohol in the driver's breath sample, then it prevents the engine of the vehicle from starting. In addition, even after the driver passes the first test and the engine starts, the device requires the driver to provide further periodic breath samples in order to ensure continued absence of alcohol.

In most states, courts are given the authority to order installation of IIDs for even first-time offenders. In addition, new laws make IIDs mandator for repeat offenders. When the court orders installation of IID, the driver must have the device installed by an authorized installer and provide written proof of installation to the court. In addition, in most states, the Department of Motor Vehicle marks the license of the driver who is ordered to install a IID with a special marker so that law enforcement officers are aware of the requirement in case they pull the driver over.

IIDs FAQs

Can a driver ordered to install the IID use a balloon or other air source to mimic human breath?

No. The IIDs currently available have anti-circumvention techniques, which cause the IID to abort phony breath samples.

Can a person with an IID restriction have someone else take the breath test sample for the driver to start the vehicle?

Not legally. Most states have laws that make it unlawful for another person to blow into an IID or to start a motor vehicle equipped with the device for the purpose of providing an operable motor vehicle to a person whose driving privileges are restricted. If the car was started illegally, the person who started it or another sober individual would have to ride in the vehicle because the unit will randomly ask for a "running retest." If a test is not taken or if the test is failed, the unit will log a violation. With some devices, the horn will honk until the vehicle is turned off. Most states have laws that impose fines and/or jail for individuals assisting in the circumvention of the IID.

Will the IID unit lose the stored memory if the battery is disconnected?

No. The unit has a back-up lithium battery to protect the data log's memory.

If a driver gets stranded and thinks the IID unit is causing the problem, is there anything he/she can do?

Some units can self-diagnose problems and the driver will be able to confirm if the unit is having problems by the condition of the service light. The driver can also call a service provider to help determine if the unit requires service.

Can a participant leave his/her car running outside of a bar, while drinking inside, and then drive away?

If someone tries to do this, the unit will randomly ask for breath tests while the vehicle is running. If a sample is not given when requested, the device logs a violation and with some devices, the horn starts to honk until the vehicle is shut off.

What happens when the driver forgets his/her service appointment?

The device will prompt the driver. For example, a device may flash or the light may stay on and a tone will sound if it needs service. If the IID is not serviced, all IIDs will enter a lockout condition and the driver will not be able to operate the vehicle. Then, the vehicle would have to be towed to the service center or the service center technician would have to perform remote service.

What if the driver is taking a medicine with an alcohol base?

Alcohol is alcohol. If the driver's blood alcohol concentration, as measured in the breath, is over the preset level, the driver will not be allowed to start the vehicle. During the training session, drivers are particularly cautioned about common substances that contain alcohol and the use of mouthwash.

What if the driver uses mouthwash in the morning and the mouthwash has an alcohol base?

Again, alcohol is alcohol. If the driver does not allow sufficient time for the alcohol to dissipate from his/her mouth, a FAIL will be registered in the memory.

What happens when a driver fails the breath test?

The IID will enter a short lockout period of a few minutes for the first failed breath alcohol test and a longer lockout for any subsequent failed breath alcohol test. This permits an opportunity for the alcohol to dissipate from the mouth and for the driver to consider the reason for the failed breath alcohol test.

Can others besides the participating driver drive the IID-equipped vehicle?

Yes. However any intended driver must take and pass a breath test in order to start the vehicle. All other possible drivers should be trained on the operation of the device. The person with the IID restriction is responsible for all readings recorded by the device.

What happens when the IID-equipped vehicle needs repair?

The driver needs to contact the IID service provider before having repairs conducted on his/her vehicle in case the repair shop has questions about the IID. Documentation must be provided if the power to the vehicle is interrupted as the unit will record the power disconnect and the reconnect.

If the IID unit malfunctions, will it shut the vehicle off?

No. The IID unit has no means of interrupting vehicle operation once it is started.

What happens if the vehicle stalls in traffic?

The IID unit permits the driver to restart the vehicle without having to conduct another breath sample, but a breath sample will be requested shortly after restarting.

What happens if the driver is out of his/her home state and experiences problems with his/her IID unit?

Most states currently have IID programs with service centers to assist them. Drivers are instructed to contact the primary service center to be routed to the closest center for assistance.

Will installation of the IID damage the vehicle?

No. The IID unit is only connected to the wiring under the dash and under the hood. At the end of the program, this wiring is restored to pre-IID installation conditions.

Will the requirements to take a "running retest" cause the driver to take his/her eyes off the road creating a hazardous situation?

No. When the IID signals for a retest, the driver has a few minutes to provide the sample or to pull over to the side of the road in a safe area to provide the breath sample. There are no buttons to push; the driver must only breathe into the unit to complete a breath sample. This is much simpler than using a cellular telephone or tuning a state-of-the-art car stereo.

How often does the device need a calibration check?

A: Typically, every 60 days.

Can the device be tampered with by computer?

No. Proprietary software and a special interface connection are needed to communicate with the device.