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Topic 6 · Alcohol, Drugs, and Driving (DUI Laws)

What does an Ignition Interlock Device (IID) do?

Why

An IID requires a clean breath sample before the engine will start, and periodically while driving. It may be required after a DUI conviction. (Handbook, Section 9.)

Practise this in the real format

Reading one answer is not the same as sitting the test. The simulator runs the first-time adult form: 36 questions, 6 mistakes allowed, 83% to pass.

Take the simulator Get the app

Source: California Driver's Handbook (DL 600, rev. 6/2025), the document the DMV writes the real test from. Edited by Fernando Aguilera. Aprobify is not affiliated with the California DMV.

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