How to install a dash cam

If you don’t already have one in your car, a dash cam is the best device you can buy. That’s because it provides video evidence – an unbiased witness – that can help prove what happened if you or someone else is involved in a collision or other bad driving.

There are many affordable options out there, and it’s a good idea to choose one that includes both a rear camera and a front-facing camera to cover the action happening behind you.

Installing a dash cam is not complicated as it is designed to be universal and fit in any car. Even if you choose to hardwire it (which means permanently plugging it into your car’s electrical system rather than plugging it into a 12V accessory outlet), it can still be a DIY job, and all of that wiring is completely reversible if you ever need it remove it from the car: there’s no cutting or soldering.

Here you will find everything you need to know. I’m using a Viofo A229 Duo as an example here, which includes front and rear cameras, but the basic process is the same for all dash cams.

1. Find your 12V accessory socket

For most people, the easiest way to power a dash cam is to use the accessory socket – which you may be familiar with from the cigarette lighter. It’s usually located in the center console or near the heater/AC controls.

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In most cars, this socket is only powered when the ignition is on, meaning it doesn’t record anything while the car is parked. A small minority of dash cams have built-in batteries to record while parked, but most require hard wiring to enable use of parking mode.

2. Plan the location and cable routing

Before you do anything, plan where you will mount the dash cam. It should not obscure the driver’s view (which may be illegal in some states or countries) and is usually best placed behind the rear view mirror on the passenger side of the vehicle.

From there, plan where you want the power cord to go to reach the 12V outlet. Typically this is at the top of the windshield, around the edge of the door, past the dash, across under the glove box and to the outlet.

If you wish to hardwire your dash cam, be sure to purchase the optional hardwiring kit and find out where the fuse box is located inside your car: this information can be found in the car’s owner’s manual.

3. Mount the dash cam

Sometimes there is a choice of suction or adhesive mounts. Always choose the adhesive mount as it will not fall off like suction cups sometimes do.

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Before actually sticking the mount to the windshield, make sure the lens is not obscured by anything, including a shadow or sunshade strip on the windshield.

Also ensure that there is enough space to connect the power cable (and the rear camera cable if you are installing a dual camera model). To do this, first connect the cables to the dash cam, and then offer them to your chosen location.

If everything is in order, remove the backing paper and press the bracket firmly into place.

4. Lay the cabling

Route the power cord from the dash cam to the outlet according to your plan from earlier.

Some dash cams come with self-adhesive cable clips that attach to the windshield or fairing, but it’s much neater to tuck the cable above the headliner and behind the plastic trim on the side of the windshield. You can either push it in or, if that doesn’t work, use a plastic cutter to carefully open a gap large enough to slide the cable in.

TIP: Instead of running the cable along the A-pillar to the bottom of the windscreen, run it to the rubber grommet that runs around the door and then down to the dashboard: preferably low enough that it can then be routed under the glove box .

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You may want to use a zip tie or two to hold the cable in place so it doesn’t dangle into the footwell.

It can be difficult to completely hide the cable from this point to the socket: it depends entirely on the design of your car’s dashboard and the location of the socket.

5. Install the rear camera

If you’ve decided on a dash cam with a front and rear camera, now is the time to attach the rear camera. The process is exactly the same as for the front camera.

Again, choose a location that doesn’t obstruct the driver’s view through the rear window, but also remember that placing the camera outside of the rear window wiper area can reduce visibility, especially in winter.

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Route the cable as directly as possible. The rear camera is usually connected to the front, which means the obvious cable route is at the top of the windscreen, along the top of the doors and then over the rear window.

If your car is a hatchback, you may need to leave a cable loop so there are enough cables to reach the camera when the tailgate is raised, as shown here.

Jim Martin / Foundry

It may be worth temporarily connecting the rear camera to the front, turning on the ignition, and holding it in place while it records a few seconds of video (or use live view in a companion app) just to be sure that the view is fine before you mount it.

Ideally, avoid having any of the rear window’s heated cables running across the center of the frame and mount the camera so that the lens protrudes between two of the cables.

6. Power on

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Insert a microSD card into the dash cam. You may need to provide your own – if so, here are some recommendations.

Now turn on the ignition and the dashcam screen should light up or LEDs should light up if there is no screen. There’s also usually a start-up sound to let you know the dashcam is recording without looking at it.

Jim Martin / Foundry

7. Adjust the settings

If your dash cam has built-in GPS, you don’t need to set the time or date: it’s done automatically. If not, you’ll need to set this up so that all video evidence shows the correct time and date. And if you live in a country that uses Daylight Saving Time, remember to change the clock every six months to keep it correct.

Other settings to check are the duration of each video clip: one minute is reasonable.

If the dashcam has Wi-Fi and a companion app, like the Viofo A229 Duo does, it’s easier to change those settings in the app.

Jim Martin / Foundry

You may also want to choose what information gets stamped (or not) on the video, such as: B. Time, date, vehicle registration number, speed and location. The latter two are only available if the dash cam has GPS.

8. Hardwiring a dash cam

You may decide you want to pay a professional to install a hardwiring kit, but it really isn’t all that difficult.

If you buy a hard-wire kit, it’s likely to have two or three bare wires: red, black, and possibly yellow, like Viofo’s HK4 kit here.

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It will have some sort of box that will serve to convert the 12V supplied by the car to the 5V that dashcams need. There may also be a slide switch that allows you to set the minimum voltage that the battery can reach before the dash cam turns off. This prevents the battery from being completely discharged when you leave the car for a long time.

In order to connect these wires to your car’s fuse box, you need to purchase what are known as “piggyback fuse holders”.

There are three different sizes, so check which type your car uses before ordering. The holders have a short piece of wire that can be crimped onto the wire from the fixed wire kit. If you don’t have a crimping tool, you can use needle nose pliers or even blunt scissors.

Jim Martin / Foundry

The red wire must be connected to a fuse with a constant power supply – even with the ignition off. Check your car’s manual for a list of fuses. Look for one that will provide power even when the ignition is off.

This could be the alarm system, the interior lights or something that obviously needs to work when the car is parked.

(You can use a multimeter if you have one and touch the probes on the two terminals of each fuse to see which read 12v with the ignition off.)

The yellow wire, if present, must be connected to a fuse that is only energized when the ignition is on. This could be the radio, 12v accessory socket or something else. Again, using a multimeter will confirm which fuses are dead when the ignition is off.

This cable is necessary as it tells the dashcam when to go into parking mode.

Once you have identified the fuses to use, locate them in the fuse box and remove them using a fuse removal tool – typically clipped into the lid of the main engine compartment fuse box.

Now slide your piggyback fuse holders in where the fuses were and slide the fuses into the slot closest to the prongs that will go into the fuse box.

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The other slot (farthest from the tines) may have a pre-installed fuse, depending on which cables you purchased. If one isn’t available, you’ll need to install one on each piggyback cable with a relatively low wattage rating suitable for a dashcam, e.g. B.5A.

The black wire usually has a spade connector on the end and is designed to clip under a nut that connects to the car’s bodywork to provide a ground connection. There’s usually a suitable one in the passenger footwell, although you may have to pull the carpet back a bit if you can’t find one.

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You will need a wrench or socket to loosen the nut enough to slip the spade under, then retighten.

You can install a hardwired kit even if your dash cam doesn’t have a park mode, but if you do, be sure to select a fuse for the red wire that does Not Have power when ignition is off, otherwise recording will continue until car battery dies.