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Guide
A G-sensor is an accelerometer that detects abrupt movement. The dash cam uses that signal to protect an event clip, but the setting must suit the vehicle and road conditions.
It is a small accelerometer that measures changes in movement across multiple axes. When the measured force passes the selected threshold, the camera marks the current recording as an event so normal loop recording is less likely to overwrite it.
The camera normally locks or moves a clip into a protected folder. The saved period varies by model, and storage is still finite, so copy important evidence promptly rather than relying on the card indefinitely.
Start with the maker's normal setting, then review genuine triggers. A very high sensitivity can treat potholes, speed humps or a closing door as incidents; a very low setting may miss a lighter contact.
It can trigger event recording while parked if the dash cam is powered and the selected parking mode supports impact detection. Some systems buffer footage before the trigger, while others wake only after it.
Frequent false triggers can fill the protected partition. Reduce sensitivity one step, make sure the mount is firm, format the card using the camera's recommended process and review storage health.
The trigger and footage can provide useful context, but a consumer dash cam is not a calibrated crash recorder. Preserve the original files and avoid claiming more precision than the device provides.
Common questions
It is an accelerometer used to detect sudden movement and flag the associated video as an event.
Use the lowest setting that still captures meaningful impacts without filling protected storage with pothole and door-closing events.
The dash cam records according to its normal mode; the G-sensor marks or triggers event footage when the movement threshold is crossed.
Many models allow it during driving, parking or both, but controls differ. Check the manual before disabling a feature that protects incident clips.
Keep exploring
The Nextbase 622GW is our balanced UK pick for its detailed recording, stabilisation and accessible touchscreen. Garmin Mini 3 suits a discreet fit, while VIOFO A329S covers the front and rear at high resolution.
A dual-camera kit is the direct choice when you want the road ahead and traffic behind in the same recording system. Check rear resolution and cable length, not just the headline front-camera specification.
The 622GW has the strongest recording specification in this trio; the 522GW keeps the large touchscreen and polarising filter at 2K, while the 322GW covers the essentials.
Start with the coverage you need: a discreet front camera for the road ahead, or a front-and-rear system for evidence from both directions. Our guides then narrow the choice by installation, connectivity and brand.