Benjamin David Howard, 20, of Bridport, pleaded guilty in the Launceston Supreme Court yesterday to having unlawfully set fire to property.

Justice Robert Pearce convicted Howard and ordered him to complete 35 hours of community service.

"It would be a pity if he, as a result of his impulsiveness and stupidity, lost the opportunity to continue his volunteer position with Tasmania Fire Service where he has, somewhat ironically, made a valuable contribution to his community over the last few years," Justice Pearce said.

Crown prosecutor Luke Brett told the court that Howard had been driving from Launceston to George Town on May 7 this year.

Mr Brett said that Howard saw an abandoned car parked by the East Tamar Highway, near George Town, and pulled over to investigate it about 10.30pm.

He said that Howard used a cigarette lighter to set fire to the fabric of a car seat.

Howard tried to flee in his car, but his vehicle would not start.

A passerby alerted police, who arrived shortly after Howard managed to start his car.

Mr Brett said that the car had been abandoned for three weeks and after the fire, only the shell remained.

Defence counsel Evan Hughes told the court that his client was remorseful and the consequences of his crime dawned on him when he later discovered the car had belonged to a person "very well known" to the court, who would soon contest a "very violent crime".

Mr Hughes said that Howard had been diagnosed with Attention Deficit Hyperactivity Disorder as a child, but stopped his medication in about year 10 because he thought it was slowing him down.