Lisa Turner and her son Jack, and Peta Cox, were killed when the BP petrol tanker decoupled and hit their two vehicles.

Wodonga based business Heavy Mechanics had serviced the truck and trailer days before the crash on the Wodonga-Yackandandah Road.

Magistrate Ian Watkins ordered the company stand trial on Wednesday after finding there was enough evidence to support a possible conviction.

He asked owner Keith Haire how he wished to plead.

“Not guilty,” he replied.

The matter followed two days of evidence last month.

The work authority had argued the service undertaken at the Kane Road business had been inadequate.

A truck component which failed hadn’t been changed for three years and had travelled about 354,000 kilometres, the court heard.

WorkSafe had argued the failed component should have been disassembled during the inspection for a more thorough examination.

But multiple mechanics had told the court it wasn’t industry practice to do so unless problems had been detected.

Mr Watkins had examined the various truck and trailer components involved in the crash during last month's committal. 

Damien Wallace, the husband and father of Ms Turner and four-year-old Jack, had attended previous hearings with other family members but was not in court on Wednesday. 

The matter will next be heard during a directions hearing in the Wodonga County Court on November 16.