Ignition Interlock Device FAQ After A DUI in Vista, California

Last Updated on June 6, 2025

If you have been convicted of drunk driving in Vista or the rest of San Diego County, you may be ordered to install an ignition interlock device (IID) in your vehicle. California law requires anyone convicted of a DUI that caused severe bodily injury or a second or subsequent DUI offense to install one of these devices. However, some counties mandate that even first-time offenders use them. Those not legally required to install an IID may still choose to do so to have their driving privileges reinstated more quickly. Whether you are at risk of a mandatory installation or are considering installing one voluntarily, it can pay to understand some basic information about these devices and the laws around them first.

What is an Ignition Interlock Device?

An ignition interlock device operates similarly to a breathalyzer test, only it has the power to stop you from drinking and driving by actually preventing your vehicle from operating. If you have such a device in your car, you will have to provide a breath sample to start your vehicle and again at a random time interval during your trip. The first breath is to make sure someone drunk is not trying to drive a vehicle, and the second is to ensure the driver did not have someone else provide a breath sample while the operator continued to drive drunk.

When an ignition interlock device is installed on your vehicle, you must provide a breath sample every time you want to start your car. If you have any alcohol in your system, the engine will not start. After the vehicle is running, you will be required to provide another breath sample at a randomly chosen point in time. This “rolling retest” is necessary to prevent an intoxicated driver from simply asking someone else to breathe into the machine.

Are These Devices Dangerous?

Ignition interlock devices randomly require a driver to submit a breath sample while driving to help ensure another person did not provide the initial sample to start the vehicle for a drunk driver. But those random samples can be a dangerous, even deadly, distraction to drivers, as one tragedy in Texas demonstrates. In this sad example, a driver stopped paying attention to the road for between 3-4 seconds while he submitted a breath test to the device. During that time, he didn’t see a woman backing out of her driveway —so he hit her at full speed. The woman died as a result of her injuries. The driver operating with the IID was not intoxicated at the time, meaning that a device meant to save lives by stopping drunk driving was directly responsible for taking a life.

Distracted driving is a real danger inherent in these devices as they require drivers to regularly take their attention away from the road. Lt. Chris Cook of the Arlington Police Department was quoted as saying, “It’s very concerning to us, as a police department, that an individual may be operating some type of ignition equipment while they’re in a moving vehicle.”

Will I Get a DUI if I Fail an Ignition Interlock Test?

When your BAC is too high when you first attempt to drive a vehicle, the ignition interlock device will prevent it from starting. You must wait a while before trying to start the car again and will be required to submit another breath test at that time. If you test positive on a rolling test or refuse to offer a breath sample, the vehicle continues operating as usual. The IID will record any rolling test failures or sample refusals.

Ignition interlock devices are legally required to be serviced and recalibrated every 60 days. If the person performing the maintenance discovers any recorded test failures, refusals to provide a sample, or evidence that you were tampering with the device, they will report these violations to the California Department of Motor Vehicles (DMV). The DMV can choose to suspend your driver’s license again if they receive any such reports.

Failure to adhere to California state law ignition interlock device maintenance requirements will also result in the installer notifying the DMV of a violation.

Who Needs to Get Ignition Interlock Devices in Vista?

Those who have received a first-time DUI in San Diego County generally don’t have to get an IID installed, but they may choose to install one voluntarily if they would like to drive before the typical six-month driver’s license suspension has ended. Other counties require all persons convicted of drunk driving to install such a device.

That being said, judges in Vista may still order a driver convicted of a first-time DUI offense to install one of these devices at their discretion. While it is still up to the judge, the San Diego City Attorney has been requesting the court to impose the installation of these devices in first offenses involving high blood alcohol levels, typically those involving a BAC above 0.15%.

Under California state law, anyone who receives a second or subsequent DUI or is convicted of a DUI causing injury will be required to install an ignition interlock device. For these offenses, the device must be left in your vehicle somewhere between 1 and 3 years, depending on the offense.

Repeat offenders are excluded if they were driving under the influence of drugs and not alcohol. Those who would otherwise be required to install an IID can be exempted from this requirement if they no longer have a vehicle or cannot use it for medical reasons.

Why Would Someone Voluntarily Install an IID?

Some first-time drivers may choose to install one of these devices willingly because otherwise, they will only be able to qualify for a restricted driver’s license allowing for travel to and from work, school, and court-mandated DUI classes. With an ignition interlock restricted license, you can drive wherever you want as long as you provide a breath sample when required. Installing an IID can also eliminate the otherwise mandatory 30-day license suspension for a first DUI.

How Much Are IIDs?

Anyone required to have such a device installed will typically be required to pay for the installation and maintenance of their ignition interlock device. On average, ignition interlock device service costs $2.50 per day, but you will also usually need to pay the company that sells it $75-100 for the initial installation, plus fees for the calibration and maintenance of the device.

The good news is that if you cannot afford a mandatory ignition interlock device because your income falls under the federal poverty line, California state law has a program that will allow you to only pay a portion of the costs.

Can I Still Drive Work Vehicles?

If you possess an IID-restricted license, you can drive a company vehicle that does not have an IID as long as you first fill out a Notice to Employers Ignition Interlock Restriction (DL 923) and give it to your employer. You must also keep a copy of the form with you or in the vehicle.

You are not legally allowed to drive any non-employer vehicles that do not have an IID installed in them.

How Long do I Need an IID?

First-time offenders only need to have an ignition interlock device installed for 6 months. Those convicted of wet reckless and ordered to install an IID will only need to have the device for 3 months. A first-time DUI that resulted in injury has a mandatory 1 year period of IID use. Most repeat offenders will be required to use the device for at least 2 years, but anyone with a prior felony will need to use it for 4 years.

Have Any Questions?

If you have been accused of driving under the influence and are curious if you will be subject to ignition interlock requirements or if installing one will allow you to reinstate your driving privileges sooner, Peter Liss can help. Please call (760) 643-4050 or (858) 486-3024. Remember that you must contact the DMV within 10 days of your initial arrest to request a hearing to stop your automatic driver’s license suspension, so it is critical you call as soon as possible.