ISS stands for "Ignition Interlock System" and appears on your California license when you are required to install an alcohol-detection device in your vehicle
The ISS notation on your California driver's license means you must have an ignition interlock device installed in every vehicle you drive. This device prevents your car from starting if it detects alcohol on your breath. The Department of Motor Vehicles adds this restriction to your license record after a DUI conviction or when a court orders it as a condition of driving privileges.
You will see "ISS" printed on the front of your physical license card and in your DMV record. It is not optional — it is a legal requirement tied to your driving privilege. Driving a vehicle without the device installed, or tampering with it, can result in criminal charges and license suspension.
Key Takeaways
- ISS means you must install an ignition interlock device in every vehicle you operate, regardless of who owns the car.
- The restriction appears on your license after a DUI conviction or court order and remains until the court removes it.
- You must have the device installed before you can legally drive, and you pay for installation and monthly monitoring fees yourself.
- Removing, tampering with, or bypassing the device is a separate criminal offense that can result in jail time and additional license suspension.
When ISS appears on your California license
ISS is added to your license in two main situations. First, after a conviction for driving under the influence (DUI) — either a first offense or a repeat offense. Second, when a court orders it as a condition of probation or as part of a plea agreement, even if the DUI charge is reduced or dismissed.
The timing depends on the court's decision and whether you are serving a license suspension first. If you are suspended, the ISS requirement typically begins when your suspension ends and you are may be able to access to drive again. If the court orders ISS without a suspension, it can begin when ready after sentencing.
The restriction also applies if you refused a chemical test (breath, blood, or urine) after a DUI arrest. California law treats a refusal similarly to a DUI conviction for licensing purposes, and ISS may be required as part of your reinstatement conditions.
How long you must have the device installed
The length of time you must use an ignition interlock device depends on your conviction history and what the court orders. For a first DUI offense, the typical requirement is 5 months to 1 year. For a second DUI within 10 years, it is usually 1 to 3 years. For a third or subsequent DUI, the requirement can extend to 2 to 4 years or longer.
The court sets the exact duration when you are sentenced. You cannot shorten this period on your own — only the court can modify or remove the ISS requirement. Some courts allow you to petition for early removal after you have completed a portion of the requirement and met other conditions, such as completing a DUI education program or maintaining a clean record.
Once the court removes the ISS requirement, you must contact the DMV to have the notation removed from your license. The DMV does not automatically update your record — you will need to provide a certified court order showing the removal.
Finding and installing an approved device
California maintains a list of approved ignition interlock device providers on the DMV website. You must use a device from this approved list — using an unapproved device does not satisfy the legal requirement. The approved providers include companies such as SCRAM Systems, Draeger, Guardian Interlock, and others.
You are responsible for finding a provider, scheduling the installation, and paying all costs. Installation typically costs between $100 and $200, and monthly monitoring fees range from $60 to $100 depending on the provider and whether you need additional services. Some providers offer payment plans if cost is a barrier.
After installation, you will receive a certificate of installation from the provider. You do not need to submit this to the DMV — the provider reports the installation directly to the court and DMV. However, keep your certificate for your records in case you need to prove compliance.
How the device works and what happens if you fail a test
An ignition interlock device requires you to blow into a mouthpiece before the engine will start. The device measures your breath alcohol content. If the reading is below the legal threshold (typically 0.02%), the vehicle starts normally. If the reading is above the threshold, the engine will not start and the device records the failed attempt.
The device also requires rolling retests — random breath tests while you are driving. If you fail a rolling retest, the vehicle will not shut off when ready, but the device will log the failure and may sound an alarm or flash lights to alert you to pull over safely.
Failed tests are recorded and reported to the monitoring company and the court. Multiple failures can trigger a violation report, which may result in license suspension, extension of the ISS requirement, or other penalties. A single failed test does not automatically cause suspension, but a pattern of failures will.
Removing ISS from your license after the requirement ends
When the court-ordered period ends, you must take action to have ISS removed from your license. The process begins with obtaining a court order for removal from the judge or court clerk who handled your case. You cannot straightforward stop using the device — you must have official documentation that the requirement has ended.
Once you have the court order, contact the DMV to request removal of the ISS notation. You can do this in person at a DMV office, by mail, or through the DMV website if your county offers online services. Bring or submit the certified court order along with your driver's license number and identification.
The DMV will update your record and issue a new license without the ISS notation if you request a replacement card. You can continue driving with your current card until it expires, but your DMV record will show that the restriction has been removed.
Common mistakes and what to avoid
The most serious mistake is driving a vehicle without the device installed while ISS is on your license. This is a separate criminal offense — not just a license violation — and can result in jail time, fines, and extended license suspension. Even borrowing a car from a family member without the device is illegal.
Do not attempt to tamper with, bypass, or disable the device. The device is designed to detect tampering, and any attempt to do so is reported to the court. Tampering charges can result in criminal prosecution separate from your original DUI case.
Do not miss scheduled maintenance or monitoring appointments with your device provider. The device requires regular calibration and data downloads. Missing appointments can be reported as non-compliance and may trigger a violation report to the court.
Do not assume the ISS notation will disappear automatically when the court-ordered period ends. You must actively request removal from the DMV with a court order. If you do not, the restriction will remain on your license indefinitely.
Frequently Asked Questions
Can I drive someone else's car if I have ISS on my license?
No. The ISS requirement applies to you as a driver, not to a specific vehicle. Every vehicle you operate must have an approved ignition interlock device installed. Driving any vehicle without the device is a criminal offense, even if you are borrowing the car from a family member or friend.
What if I cannot afford the installation and monthly fees?
Some device providers offer payment plans or reduced fees for financial hardship. Contact approved providers directly to ask about options. You can also request a fee waiver or reduction from the court if you can demonstrate financial need, though approval is not may provide. You must still install the device to legally drive.
Does ISS on my license affect insurance or employment?
Insurance companies can see ISS on your driving record and may increase your premiums or deny coverage. Some employers may also see the restriction depending on the type of job and whether they conduct background checks. This varies by company and policy, so contact your insurance agent and employer directly if you have concerns.
Can I get the ISS requirement removed early?
Only the court can remove or modify the ISS requirement. Some courts allow you to petition for early removal after completing a portion of the requirement and meeting other conditions, such as finishing a DUI education program or maintaining a clean driving record. You would need to file a motion with the court that sentenced you and attend a hearing.
What happens if I move out of California while ISS is on my license?
If you move to another state, you must still comply with California's ISS requirement. You will need to install an approved device in your new state and maintain compliance with California law. Some states have reciprocal agreements with California, but you should contact both the California court that ordered ISS and your new state's DMV to understand your obligations.