Dashcam goes flat in the car

[smart51]

My dashcam is behaving strangely. If I take it out and plug it in to a phone charger, the battery symbol shows that it is charging up. It then works in the car for a few days. What is odd is that it switches on with the ignition, and switches off if I unplug the USB cable, but it won't charge up using the in car USB cable, it just shows the low battery symbol. How can a USB cable supply enough power to switch it on, but not enough for it to work?

[dudleybloke]

Try a different cable, I had similar with my phone charging cable a while back.
If you have a USB power meter you could use it in line and see if its the lead or socket.

[smart51]

It is a 12V USB supply that is wired into the fuse box. I guess I could get a new one. I don't have a USB power meter.

[Scrump]

I have had similar with my old satnav. It turned in with the ignition and even showed the charge symbol but wasn’t actually charging. A different cable sorted it for me.

[vikingaero]

How long have you had it? Many dashcam batteries go kaput and enlarge after a few years as they slowly fail. Nextbases are notorious for this. Most decent new dashcams use capacitors.

[smart51]

I've had it a few years. I've tried two 12v car to USB leads. Neither will charge either my dash cam or my tablet. Both can be charged with a 240v charger.

[Mars]

Can you check the voltage presented at the end of the cable? Tricky if it exits via a USB connector, but your car might not be presenting enough to charge the device. And that might not be the car's fault as others have mentioned (cable) but worth comparing with what the cam sees when plugged into the home charger.