An Adelaide man has been issued with a caution and a fine for modifications to his car, including a solar panel on the bonnet and gas bottle attached to the rear.

Key points: An Adelaide driver has been cautioned after a solar panel and gas bottle were detected on his 4WD

An Adelaide driver has been cautioned after a solar panel and gas bottle were detected on his 4WD His vehicle was defected by police and it will need to pass an inspection

His vehicle was defected by police and it will need to pass an inspection He also received a fine of $752 for a "mutilated" number plate

Just before 10:00am on Saturday, police spotted the Toyota four wheel drive travelling on Belair Road, south of Adelaide, with a solar panel fitted to the bonnet and a gas cylinder attached to the spare tyre holder at the rear.

Police also discovered that the driver's number plate had been cut in two.

He was handed a fine of $752.

Road Policing Tactical members were conducting a traffic operation when the vehicle was spotted with what a police described as "potentially dangerous" modifications.

A 56-year-old man from Brooklyn Park was issued with the fine for the mutilated number plate and was instructed to remove the solar panel and gas bottle from his vehicle.

The four wheel drive was also defected and will need to pass an inspection at a recognised inspection station.

"These illegal additions create a significant safety risk in the event of a collision and SAPOL would like to remind motorists that any object fitted to a vehicle must be designed, built and fitted to the vehicle in a way that minimises the likelihood of injury to a person making contact with the vehicle," Brevet Sergeant David Williams of the Road Policing Section said in a statement.

"Any fittings, hooks or attachments must not have any sharp edges, corners or protrusions."

The Department of Planning, Transport and Infrastructure's vehicle standards state that no vehicle can be equipped with any object or fitting not technically essential to the vehicle.

It also states that no vehicle is allowed to be equipped with any object or fitting which — because it is pointed or has a sharp edge — is likely to increase the risk of bodily injury to any person.

In 2016 a 32-year-old man was caught driving an unregistered car which had a metal pan instead of a steering wheel.

That car was impounded for 28 days.