ISS stands for "Ignition Interlock System" — a device that prevents your car from starting if it detects alcohol on your breath
When ISS appears on your California driver's license, it means you are required by law to install and maintain an ignition interlock device in any vehicle you drive. The device connects to your car's ignition and requires you to blow into a breathalyzer before the engine will start. If the device detects alcohol above a set threshold (usually 0.025 percent blood alcohol content), the car will not start.
ISS is not optional. It is a court-ordered condition tied to a DUI or wet reckless conviction in California. The Department of Motor Vehicles (DMV) places the notation on your license to inform law enforcement and you that the restriction is active. Driving without the device installed, or tampering with it, is a separate criminal offense.
Key Takeaways
- ISS on your California license means you must have an ignition interlock device installed in every vehicle you operate.
- The device is court-ordered following a DUI or wet reckless conviction and is not a choice.
- You must use the device every time you drive, and it records all breath tests and attempts to start your vehicle.
- Removing, disabling, or bypassing the device is a criminal offense separate from your original conviction.
- The ISS requirement remains on your license for a set period determined by the court, typically one to three years depending on your conviction.
How the ignition interlock device works
The device is a small breathalyzer unit wired into your vehicle's ignition system. When you get in the car, you blow into the mouthpiece. The device analyzes your breath alcohol content and either allows the ignition to engage or locks it out. If alcohol is detected above the threshold, the engine will not turn over, and the device logs the failed attempt.
Even after the car starts, the device requires rolling retests — random breath tests while you are driving. If you fail a rolling retest, the vehicle's lights and horn set up to alert you, though the engine does not shut off while moving. The device records every test result, every start attempt, and every failure. These records are downloaded monthly and reviewed by the monitoring company and the court.
You pay for the device installation and monthly monitoring fees, which typically range from $60 to $150 per month depending on the vendor. California-approved vendors include LifeSafer, SmartStart, and Alcohol Monitoring Systems (AMS). The court will direct you to an approved provider.
When ISS appears on your license
The DMV adds ISS to your license after a DUI conviction (Vehicle Code 23152) or a wet reckless conviction (Vehicle Code 23103.5). The notation appears on the front of your physical license and in the DMV's electronic records. It stays there for the entire duration of the court-ordered restriction period.
For a first DUI offense in California, the court typically orders ISS for six months to one year. For a second or subsequent DUI within ten years, the requirement is usually one to three years. The exact length depends on the judge's decision at sentencing and whether you have prior convictions.
You cannot remove the ISS notation yourself. Only the court can order it removed, and only after you have completed the full restriction period and provided proof to the DMV that the device has been uninstalled.
Your responsibilities while ISS is active
You must have the device installed before you drive. Driving without it installed while the restriction is active is a violation of your license restriction and can result in arrest, additional criminal charges, and license suspension. You cannot claim you forgot or did not know — the ISS notation on your license is your legal notice.
You must pass the monthly monitoring checks. The device vendor downloads your breath test records and violation history each month. If you have failed tests, missed rolling retests, or attempted to tamper with the device, the vendor reports this to the court. The court may extend your ISS requirement, impose additional penalties, or revoke your license.
You must pay all monitoring and maintenance fees on time. If you fall behind on payments, the vendor may report you to the court, and your license can be suspended. Some counties offer fee waivers or reductions based on income — ask the court or your vendor about this option.
What happens if you tamper with or bypass the device
Tampering with, disabling, or attempting to bypass the ignition interlock device is a separate criminal offense under California Vehicle Code 23247. This includes having someone else blow into the device for you, disconnecting wires, or using a device designed to trick the breathalyzer. Conviction for tampering carries jail time, additional fines, and automatic license suspension.
The device is designed to detect tampering. It records attempts to disconnect it, unusual patterns in test results, and signs of physical interference. These records are reviewed monthly and reported to the court. Even a single detected tampering attempt can result in criminal charges.
How to get ISS removed from your license
You cannot remove ISS early. You must complete the full court-ordered restriction period, which is typically one to three years depending on your conviction. During that time, you must pass all monthly monitoring checks and maintain a clean record with the device.
Once the restriction period ends, you must obtain proof from the device vendor that the unit has been uninstalled. Bring this proof to the DMV along with a completed form DL 44 (process for California Driver License). The DMV will issue a new license without the ISS notation. There is no fee for this replacement.
If you believe the ISS notation was placed on your license in error, you can request a hearing with the DMV. Contact your local DMV office and ask to speak with a supervisor about contesting the restriction. You will need documentation from the court showing that your conviction was overturned or that the ISS requirement was removed.
ISS versus other license restrictions
California uses several notations on driver's licenses to indicate restrictions. ISS is specific to ignition interlock requirements. Other common restrictions include "DL" (daylight driving only), "CR" (corrective lenses required), and "M" (motorcycle only). ISS is one of the most serious because it directly prevents you from operating a vehicle without compliance.
Some drivers with DUI convictions may be ordered to use an alcohol monitoring ankle bracelet instead of or in addition to ISS. That is a separate court order and appears differently in your DMV record. ISS is specifically about the vehicle; the ankle bracelet monitors your alcohol consumption at all times.
Frequently Asked Questions
Can I drive someone else's car if I have ISS on my license?
No. The ISS restriction applies to you, not to the vehicle. You cannot operate any vehicle without an approved ignition interlock device installed, regardless of who owns it. If you drive a car without the device, you are violating your license restriction and can be arrested.
What if I fail a breath test while driving?
A failed rolling retest triggers your vehicle's lights and horn but does not shut off the engine while moving. You should pull over safely. The failure is recorded and reported to the monitoring company. Multiple failures in a short period may result in the court extending your ISS requirement or suspending your license.
Can I get the ISS requirement waived or shortened?
Only the court that imposed the requirement can modify or remove it. You can petition the court for early removal, but this is rarely granted unless you can show extraordinary circumstances. Most courts require you to complete the full restriction period without violations.
What if I cannot afford the monthly monitoring fees?
Contact the court that ordered the ISS requirement and ask about fee reduction or waiver programs based on income. Some counties have hardship provisions. You can also ask the device vendor about payment plans. Falling behind on fees can result in license suspension, so address this when ready.
Does ISS appear on my driving record that employers see?
ISS appears on your DMV record, which employers may see if they run a background check. However, the specific reason for the restriction (DUI conviction) is separate information that appears on your criminal record, not your driving record. Employers typically see both if they conduct a thorough background check.