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Hardwiring a dash cam - not enough power reaching device?

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I've bought a new (to me) car and the location of the cigarette lighter socket means it's better for my old dash cam to be hard wired.

Handily there was a Youtube video of my exact model of car and on the face of it it's a very simple install - £10 kit from Amazon, remove an accessory switched fuse, put that fuse into the empty piggyback fuse spur, plug spur into slot that's just vacated, plug spur in to the device and earth the black wire behind a bolt. In theory a 5 minute job but it's taken me hours due to struggling to loosen/tighten the earth bolt as it's so hard to get to.

I used the exact same fuse as the Youtube video (in the car handbook it says Reversing lamp - Fuel injection system - Audio system -VSC system) which was an orange 5A one.

The dashcam powers on when the ignition starts but it doesn't start recording. the power light almost seems like it's struggling to stay on and the screen goes blank, however when plugged into the cigarette lighter with the original lead it works as it should - turns on with the ignition, starts recording and the screen stays on for 3 minutes but it continues recording, as denoted by the flashing lights. I've plugged the dashcam into a regular USB socket inside and it works exactly as it should so it's almost as if the hardwire kit isn't giving it enough power to function fully?

The hardwire kit says:

Input voltage: DC 12v-24v

Output voltage: DC 5V

Output current: 2A

The dashcam is a Mio MiVue 518. It says input 5v followed by a solid line at the top with three dashes underneath then 1A

Initially I had the ground wire attached to the top bolt in the photo but that didn't work at all (no power whatsoever when camera plugged in) perhaps due to the plastic cover, so changed it to the screw in the photo but when this didn't work as it should I used the same earth bolt as in the Youtube video which is hidden up near the fuse box - the issue described above is the same with both the screw earth point and the bolt earth point near the fuse box..

Any suggestions? I don't have a multi meter, I was going to get one from Amazon but they just look so confusing! I don't mind buying a new dash cam if needed but it seems strange that my old one works fine from the cigarrete lighter and indoor USB but not from the hardwire kit.

Photos of the fusebox if helpful, I've tried the spur facing forwards and backwards.The purple 3A fuse came with the kit and the orange 5A is the one I removed from the fusebox.

The kit from Amazon was this one, gets decent enough reviews and nobody complaining of a similar issue.
Would be gratetful for any input


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Run a temporary wire to a known ground in the engine bay, if it functions this points to a bad ground.
Thanks, the black wire is definitely attached to a known ground bolt - a) the bolt I have it attached to was in the Youtube video from a guy who installs these professionally and b) it has E on the bolt for earth.
A known ground in the engine bay will be the engine block or battery negative terminal. You need a wire from here to your connected black ground wire, if it functions like this your original ground connection must be poor.
A known ground in the engine bay will be the engine block or battery negative terminal. You need a wire from here to your connected black ground wire, if it functions like this your original ground connection must be poor.

Thanks, I'm not very technical at all - was proud of myself for even attempting this - and I don't have any spare wire to do this test so will just have go back to using the cigarette lighter socket
you could use the -ve terminal of the cig. lighter as an alternative ground.
cig.loghter will have a +ve to center and a -ve to metal casing. this -ve is connected to chassis as a ground
You need a temporary connection to verify if your existing ground is good or bad. Imagine a drawing where you put a dotted line from one place to another, the dotted line needs to be from a known ground as previously mentioned to your black wire but the dotted line needs to be a piece of wire.
Thinking about the ground point I used (as suggested in the Youtube video) there was already something attached to it so I slipped my U shaped cable on top of it - so they're essentially stacked under the bolt - should I have placed it under? If yes would that affect the things that's already attached?

The grey wrires with the large metal piece are what was there before, my U-shaped metal ring went on top of that underneath the bolt.

As others have said you need to confirm with a good ground (this could be from the battery negative terminal for example),

although the bolt you have used is a grounding point it could have some corrosion etc adding resistance meaning not enough current can flow.

Think of it as if the 2 wires that were connected to the bolt already are 2 taps on a sink, the drain on the sink (the bolt) can only just cope with the 2 taps turned on as it is partially blocked but now you have added another tap the water cant drain fast enough so the sink starts to fill. So the drain needs unblocking, its a very simplified way of looking at it but hope it makes some sense

What you could do is take the hard wire kit out, and using some clip or similar connect it directly to the battery (with a fuse) and see if it works this will prove if the fault is with the hard wire kit wiring or with the wiring you are tapping into in the car, then afterwards you can try the positive from the fuse box as its connected now and run a cable to the battery negative terminal to tell if its the + or - at fault as Dave said although you do need a cable for this

If it is the earth at fault, removing the the bolt/nuts etc and giving it a good clean should work, if not you can always make yourself a new earth point by putting a nut and bolt anywhere on the car body

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