Words by Ramsay Beacham
Photography by Lachlan Payne

It’s an age-old problem that has been around for about as long as the motor vehicle itself, or at least since the introduction of parallel parking. It’s called parking a large vehicle in a small space between two other vehicles, and it isn’t always easy.

Even when you’ve mastered the art of swinging into one of these parks, there’s still the question of how far you can reverse before you hit the vehicle behind. You can check your mirrors and twist your neck until the cows come home, but short of getting out and taking a gander, it’s still nigh on impossible to tell how far you are from the car behind – until now.

Reverse-parking sensors are being fitted to more and more of today’s new 4WDs in an ever-increasing attempt to improve safety and practicality. After the realisation that this sort of technology would be useful to everyone, and not just those who can afford a fairly highly specced 4WD, there is now a DIY kit available for retrofitting to any vehicle, new or old, including 4WDs.

The DIY kit comes with most of the hardware you’ll need to do a neat job, including double-sided tape, zip ties and even a hole saw.	After cracking open the tail-lights, I found that the wires leading to the reversing light were conveniently coloured red and black. A couple of scotch locks later and we have power.

What's involved?

The DIY reverse-parking sensor kit from SuperCheap Auto comes with all the necessary hardware needed to perform a generic installation. This includes the main electrical components, mounting screws, double-sided tape, zip ties and in this case even a hole saw to drill the holes for the sensors.

Four sensors are supplied for fitment into the rear bumper, but the system can operate with as little as two. After drilling some suitably spaced holes (as specified by the instruction page) in your bumper bar, these sensors simply push into place and a locking ring can be used on the back to secure them further.

Use the provided hole saw to drill out some suitably placed holes in your rear bumper bar. Make sure there’s nothing important behind it, though.	The instructions specify that if you’re installing all four sensors, then the distance between the middle two should be 0.4 times the distance between the outer two.!

The provided zip-ties can then be used to neatly route each of the individual leads through a rubber grommet into the body and towards the central control unit.

The digital display can be mounted anywhere in the vehicle via a bit of the good old double-sided tape. A good place for this is above the rear window, where it is easily seen either in your rear vision mirror or by looking around and is out of harm’s way. If you’re really keen, there’s enough spare lead to run the display right up to the dash, or above the rear vision mirror where it can remain in plain view.

With the perfectly sized hole, the sensors should be a neat fit. Plastic rings are supplied to theoretically secure them even better, but I found that a couple of them wouldn’t fit.	There’s enough cable to run the display up to your dash if you’re keen, but it’s out of the way and easy to see where I mounted it above the rear doors of the dirty GQ.

Both a digital distance and an optional audible beeper are displayed, which will increase in frequency as you move closer to an object before flat lining with a constant noise at a distance of 0.3m. I’ve found this to be more use than the display itself as it allows you to concentrate on the other aspects of parking.

The most logical and convenient place to draw power for this particular application is the reverse lamp. This means the system will only operate when the vehicle is in reverse, which makes sense as it’s the only time you need it really. This also helps keep wiring to a minimum, as the reverse lamp is already fused and can be drawn from directly.

All the sensors and the display merge into this little control module. I tucked it away neatly behind the inner skin of the body, just in front of the tail-light.	A zip-tie here, a zip-tie there, and I’m back in business. Now, hopefully the hit-and-run rate in Sydney will fall slightly.

The sensor, display and power wires all run to a central control unit that is best mounted out of harm’s way behind the inner panel skin. Although, the kit supplies enough wiring to mount it just about anywhere.

There it is – one DIY project down, only half a few thousand more to go. Hopefully, from now on, I won’t have to spend five minutes out the front of work every morning scanning for car spots that are usually only suitable for small Suzukis and the likes.

DIY vs Pay by the hour

The reverse-parking sensor I bought down at SuperCheap Auto set me back $119 exactly, and took around three hours to install – remembering that this was during work hours. Add around four hours labour for a professional fit, so at $80/hour that’s a grand total of around $440 inclusive.

The other scenario requiring ‘pay by the hour’ involves a panel beater, and it’s not cheap. You’d be surprised how even the smallest nudge can cost the earth to repair, not normally for your own vehicle, but for the feeble little Getz that you couldn’t see behind you.

It’s generally going to cost a minimum of $400 worth of insurance excess, but add around another $450 to that if you’re less than 25 years of age. That’s more than seven times what it’ll cost you to install a reverse-parking sensor.

Alternatives

One alternative to the reverse-parking sensor is a replacement beeping reverse light – great for letting pedestrians know that you’re backin’ up, but highly unlikely to stop you from reversing into a parked car.

Alternatively, you can wire-up a full-size beeper yourself, or you could go the whole hog and get a reversing camera with TV screen. This has the added benefit of allowing you to line up trailers by seeing exactly what is behind you. The downside is that they are considerably more expensive to buy, and in the case of the ’88 GQ Patrol, this might be a bit of an over-capitalisation.

Both the beeping-bulb and full-size beeper sell at SuperCheap Auto for $20 a pop, while a reverse-camera kit will set you back around $299.