A Bringelly bus company mechanic has admitted he may not have checked the brakes on a Starliner coach just days before in was involved in a fatal crash near Kangaroo Valley in 2010.
The 53-seater bus was ferrying passengers down Barrengarry Mountain on the evening of May 14 when its brakes failed, causing the vehicle to crash through a guard rail and plunge into a ravine.
Graham Lees, the owner of G&S Minibuses and who was driving at the time, was killed in the crash while several passengers were injured.
Mr Lees' son, Simon Lees, and heavy vehicle certifier Stuart Lewry, are on trial in Wollongong District Court charged with involuntary manslaughter by gross negligence; Lees is accused of allowing the vehicle to be used knowing the brakes were faulty, and Lewry of signing off on the vehicle's roadworthiness without inspecting it.
G&S's in-house mechanic, Michael Fassoularis, took the stand on Monday, telling the court Graham had asked him to work on the bus' braking system after it was defected by the RTA on May 3.
He initially told the court he "did what Graham asked me to".
"You said you made a physical adjustment on the brakes," Mr Fox said, referring to what Mr Fassoularis told police in a 2011 statement.
"Yes," he replied.
However, when pressed for details of the repair work carried out, Mr Fassoularis was unable recall what work he'd done or even what tools he used, prompting Judge Andrew Haesler to ask if he had any recollection of being under the bus to work on it.
"A vague one, your Honour," Mr Fassoularis replied.
Mr Fox told the court experts were expected to give evidence later in the trial that the bus' brakes were covered in dirt and grime and showed no signs of recent work.
"Could you not have adjusted the brakes on this occasion?" Mr Fox asked Mr Fassoularis.
"You're raising a doubt, it could be right," he responded.
Mr Fox: "You’re saying it’s possible you didn’t adjust the brakes?"
Mr Fassoularis: "Possibly."
Meanwhile, the bus' previous owner, Stephen Golding, said he had the vehicle serviced every 5,000km and described it as being in "perfect" mechanical condition when he sold it to Graham Lees in December 2008.
The trial continues.