Blog Articles > Twin lens RVS794 Reversing Camera to Motorhome

Fri, Nov 23rd 2012

Today we are installing the Waeco RVS794 Camera system to a Hymer B774 A-class for Lyn & Andrew Glossop.  This is a recent purchase for them and fitting a reversing camera was top of their list of things to do.  As you can see from the photos, this motorhome has a no rear window and a bike rack on the back which makes reversing really tricky!

Hymer A Class Image left: Hymer A Class

This system includes the NEW CAM44 twin lens camera with the M7L 7 inch monitor and as we are a Dometic Motorhome Centre there is a 3 year warranty on the product.

Close up of CAM44 on Hymer A ClassImage right: Close up of CAM44

Having no rear window means that the driver is fairly blind which is where the twin lens camera really comes into its own.  The second lens means that even while in a forward gear the monitor displays the narrow angle lens which looks down the rearward road.  The camera has a motorised shutter that covers the reversing lens when in a forward gear or when its switched off, this stops the lower lens from getting mucky.  There is a hole in the shutter so the upper, narrow angle lens can peek out through it.

Closeup of M7L showing narrow distance view


Image right: Monitor showing distance rear view

When the gear is changed to reverse, the camera will automatically switch to the wide angle downward facing camera, just like that!  It is possible to switch between the two camera angles without changing gear, simply by pressing the V1/V2 button, very handy if you have someone right in the blind spot!

Closeup of M7L showing rear view and distance markers


Image left: Monitor showing reversing view

One other great feature of this system are the distance markers that appear on screen when in reverse.  These markers act as guides to show where in the picture your vehicle will be when you reverse, they can be adjusted to suit the van dimensions too.  If you mainly drive a car and only drive your motorhome for a few weeks of the year, this can be a great help with spatial awareness.

The camera is mounted centrally about 6 inches below the height of the roof (to avoid being swiped by low tree branches!).  The cable from the camera is run down inside the wardrobe in some conduit, through the floor and then along the underside of the chassis (neatly clipped up out of the way).

Rear of Hymer A Class showing roof rack and CAM44Image right - CAM44 showing bike rack

The camera cable is then brought through into the dash area and connected on to the M7L Monitor wiring loom.  Usually on coach built motorhomes we would bring the cable up through the drivers side step but this A-Class is more tricky as there is no drivers door, hence the spaghetti of wires and having to remove half of the dashboard!

Hymer Dashboard camera wiring

Image above - Dashboard spaghetti, threading the wiring across the dashboard

We mount the monitor on the right hand side of the driver between the steering wheel and the right wing mirror.  This becomes a natural place to look from the wing to the rear without having to turn your head and adjust your focus.

Hymer steering wheel with M7L installed

Image above - Steering wheel view with monitor in position

Lyn & Andrew were really happy with the installation and are looking forward to reversing the motorhome without that blindfolded feeling.  We hope to see them both soon for the next project.

One thing to remember when cleaning a vehicle fitted with a reversing cameras is not to jet wash in the camera area.  The camera is fully waterproof but the seals can't withstand water under pressure.  Occasionally you may get an eight legged hitch-hiker that will look HUGE on the monitor, these you can just brush away, if you're brave enough!

This booking was taken from the NEC Motorhome & Caravan show last month at our special show price of £769 including installation - usually £834 inc install. See our show calendar to find out where we are exhibiting in 2013.

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