Common questions and answers in relation to vehicle specifications.

What do the inspectors check for when my defected vehicle has a roadworthy inspection?

Does my windscreen demister have to work?

Vehicles built from 1971 need a working demister to work on the front windscreen. There is no requirement for a rear demister to be fitted. For more information see Defective vehicles in South Australia (280.9 KB PDF)

Does my car need to be fitted with a working windscreen washer?

All passenger vehicles manufactured after 1972 must have windscreen wipers that have operative windscreen washers. Defective vehicles in South Australia (280.9 KB PDF)

How many driving lights can I have on my motor vehicle?

A maximum of four driving headlamps are permitted on a motor vehicle in addition to the standard headlamps. The lights must be wired so they only operate with the vehicle's high-beam lights. The mounting of these lights must be at the front of the vehicle. For more information see Cars - Lighting and instrumentation

I don't like the convex mirrors that have been fitted to my new vehicle can I take them off?

Yes, and they can be replaced with a flat mirror of the same size.

Can I fit nitrous oxide injection to my vehicle?

Nitrous oxide injections systems must not be fitted. This also includes any partial installation or any that can be disconnected.

Does my speedometer have to work?

All motor vehicles manufactured after June 1988 must have a functioning speedometer calibrated in kilometres.

Can I buy a second-hand seat belt?

No - it is illegal to sell a second-hand seat belt. For more information see Cars - Seats and seat belts

Can I fit retreads to my vehicle?

Retreads can only be fitted to vehicles where the retreaded tyre casing has a load rating equal or greater than that specified on the tyre placard. For more information see  Cars - Wheels and tyres

Can I fit tyres or tread patterns on my car that are different from what is already on the vehicle?

Passenger cars and derivatives manufactured before 1973 may be fitted with tyres which are of a different carcass construction provided the tyre carcass type across any axle is the same. If there is a mix of conventional and radial ply tyres the radials should be fitted on the rear axle. A passenger car or derivatives manufactured after 1972 must be fitted with tyres of the same carcass as specified by the vehicle manufacturer on the tyre placard. The tread pattern does not have to be the same on each tyre. For more information see Cars - Wheels and tyres

Do I need a spare wheel or a jack for the roadworthy inspection?

No - although it is advisable.

When can I use the fog lights on my vehicle?

Use fog lights when driving in fog or other hazardous weather conditions. Using them at other times is an offence. For more information see  Cars - Lighting and instrumentation

Can I sell my defected vehicle?

Yes - you may sell a defected vehicle provided that it is for the purposes of dismantling or wrecking, and the registration is to be cancelled. Defective vehicles in South Australia (280.9 KB PDF)

Can I fit spot lights to the roll bar on my 4WD?

Yes. Providing the light or lights are facing forward and don't obscure the drivers view of the road. The lights are to be fitted so that they do not dazzle the driver or any other road user either directly or indirectly eg. through the rear view mirrors and or other reflecting surfaces of the vehicle. For more information see Cars - Lighting and instrumentation

Can I fit coloured under-car neons to my vehicle?

No - you cannot show coloured light other than what is specified in the Road Traffic (Light Vehicle Standards) Rules 2018, and the Australian Design Rules. For more information see Cars - Lighting and instrumentation

Can I put a battery in the boot of my vehicle?

You may fit a battery in the boot of your vehicle provided that it is securely mounted in a battery box. If it is a battery that emits fumes it must be vented externally to the atmosphere. If the battery is a sealed type there is no requirement to have it vented to the atmosphere.

Contact Vehicle Standards



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Page last updated 31 May 2022

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