The troubleshooting order
Why your dash cam isn't recording everything
Three things actually stop a dash cam recording the way it should: the card is full of locked files with no room left to loop into, the card has failed or is the wrong class for the bitrate it's being asked to write, or the camera loses power altogether because it only runs off the cigarette lighter and the ignition is off. Work through them in that order, because the first check costs nothing and the last one costs the most time.
Is the card full of locked files
Open the card's file list, in camera or on a computer, and see how much of it is taken up by locked or protected clips rather than ordinary loop footage. If locked files have eaten most of the card, that's very likely your answer: see how long footage lasts and how loop recording is supposed to work for why this happens. The fix is to review your locked clips and delete or unlock the ones you don't actually need.
Has the card failed, or is it the wrong class
If storage looks fine but recording still fails, or clips are corrupted or missing frames, try a different card you know is good and see if the problem follows the camera or the card. A card's speed class matters too: one too slow for the bitrate the camera writes can drop frames or fail to keep up, particularly at higher resolutions.
Is the camera losing power with the ignition off
If recording appears to fail specifically while parked rather than while driving, the likely cause is power, not storage. Plugged into the cigarette lighter alone, most dash cams lose power the moment the ignition turns off. See does a dash cam record when the car is off and which fuse to use for wiring it properly with a hardwire kit on a fuse that stays live.
SD card reality: why cards wear out
Flash memory in an SD card has a finite number of write cycles per cell. Loop recording writes and overwrites the same physical area of the card constantly, a far harder workload than typical photo or document storage. That's the reason high endurance cards exist, built and rated specifically for the continuous rewrite pattern dash cams and security cameras create, in a way an ordinary consumer SD card is not.
Reformat in camera monthly
Reformatting through the camera's own menu, not a computer, rebuilds its file system and clears the fragmentation that constant loop writing builds up. That's why manufacturers and forums both treat a monthly reformat as routine maintenance rather than something to do only once a problem shows up. Reformatting erases the card, so copy off anything you want to keep first.
Questions
Why has my dash cam stopped recording?
The three real causes are a card full of locked files with no room to loop into, a card that has failed or is the wrong class for the bitrate, or the camera losing power because it only runs off the ignition circuit. Check them in that order: it costs nothing to look at the card first.
Why won't my dash cam overwrite old files?
Usually because the space it sets aside for locked or protected clips has filled up, leaving no room for the loop to recycle into. Review your locked files and delete or unlock the ones you don't need.
How do I know if my SD card has failed?
Swap in a different card you know is good and see whether the problem follows the camera or stays with the card. Corrupted clips, missing frames or files that won't play are the usual signs of a card that has failed or is the wrong class for your camera's bitrate.
Do I need a special SD card for a dash cam?
A high endurance card is built for the specific workload a dash cam creates: constant rewriting of the same area of the card through loop recording, which wears out an ordinary consumer SD card faster than typical photo or document use would.
How often should I reformat my dash cam's SD card?
Monthly, done through the camera's own menu rather than a computer, is the routine maintenance point both manufacturers and dash cam forums point to. It clears the fragmentation that constant loop writing builds up. Copy off anything you want to keep first, because reformatting erases the card.
Last reviewed 10 July 2026