Abstract: Road accidents caused by drunk driving are a major public safety concern worldwide. The Alcohol Sense Engine Locking System is designed to prevent such incidents by detecting alcohol levels in a driver’s breath and automatically disabling the vehicle’s ignition system if alcohol is detected beyond a safe limit. The system uses an MQ-3 alcohol sensor to measure the presence of alcohol from the driver’s breath.

The sensor output is processed by a microcontroller such as Arduino Uno, which compares the detected value with a preset threshold level. If the alcohol concentration exceeds the permissible limit, the controller activates a relay module that locks the engine ignition system and triggers an alert through a buzzer and display unit. If no alcohol is detected, the engine is allowed to start normally

This system enhances road safety by preventing intoxicated individuals from operating vehicles. It is cost effective, reliable, and suitable for integration into modern vehicles as a preventive safety mechanism.

Keywords: Sensors, Real-Time Monitoring, Safety.

Downloads: | DOI: 10.17148/IJIREEICE.2026.14351