Do you need fast set up and interlock install? phone iconCALL US ON 0800 002 182

nz owned logo

What is an interlock?

What is an interlock?

Do you need to get an alcohol interlock installed to get back on the road? No doubt you’ve got some questions about how an interlock works? Go no further! In this article we’ll explain all you need to know about interlocks and how they work.
Smart Start Interlocks has been installing interlocks in New Zealand since 2013. Since then we’ve gone from installing hundreds of interlocks per year, to thousands.


What is an interlock and how do they work?

An interlock, also known as an alcohol interlock, is a breathalyser that is wired into the ignition of your vehicle. With an interlock installed, a vehicle is unable to start until an alcohol free breath sample has been provided.


Interlocks measure breath alcohol concentration (BrAC). In the event a person trys driving with alcohol in their system, the interlock will not allow them to start their vehicle, meaning they will need to find alternate transport.

Smart Start’s interlocks use fuel cell technology, the same technology as Police breathalysers, meaning alcohol readings are reliable and accurate. 


Interlocks are a similar size to a smartphone and are discreetly installed near the drivers seat to avoid drawing attention.


Do you know need to use your interlock to start your vehicle?

When using an interlock, there are two different tests to be aware of. The initial test, and rolling retests.


Initial tests are the tests that must be taken before the vehicle will start. Once you turn your ignition on, the interlock will initialise and call for a test. Different interlock providers have different blowing techniques to ensure it is an ‘actual person’ bowing into the interlock, and not just a bag of air.


Smart Start’s interlocks provide a very easy (and sanitary) blow-hum. You blow into the interlock while saying the word ‘who’.  Some providers require a blow and then a suck. We’ll let you decide which option you’d prefer!🤢


Initial tests prove you have not got any alcohol in your system, and that you’re safe to drive. Once the initial test has been passed, you start your vehicle and begin your trip.


Rolling retests will occur randomly while you drive. These are to prove that you have not had anything to drink since starting your vehicle. 


When an interlock calls for a rolling retest, you typically have 5 minutes to complete the test. If you’re not comfortable taking the test as you drive, this allows plenty of time to find a safe place to pull over.


In the event you fail or skip a rolling retest, the interlock will NOT turn off your vehicle. However, any failed or skipped tests are recorded and will likely lead to an extension of your interlock programme, so it’s very important you complete them all as required.


Why does my interlock need servicing?

During a monthly service, the technician will check your interlock, perform any necessary updates, download the interlock data, and perform a calibration to ensure the interlock is accurate.


Servicing takes approximately 15min and can be done at any of our service centres nationwide.


Your interlock service is due every month on the same day as your interlock was installed. You have a 7 day grace period each side of that date, don’t leave it to the last minute. If you miss your monthly service, your interlock will lock out and you won’t be able to start your vehicle. 


How to get started?

Getting an interlock installed is very easy. Call us on 📞 0800 002 182 (we’ll answer within 30 seconds) to set up a file. Provided you have got the information required, we can have an interlock installed within a day, subject to our service centre availability. 


Our friendly call centre based in Maungaturoto is available from 7–5 from Monday to Friday. We have an emergency afterhours helpline if you require assistance outside business hours. 


It’s our mission to make the interlock programme as quick and easy as possible. We’d love to help!❤



Share Now