Boy actor James Rolleston has pleaded guilty to causing a crash which left him and his friend seriously injured in July last year.

The 19-year-old appeared at the Auckland District Court this morning before Judge Nevin Dawson.

Supported by his family, the actor officially entered his guilty plea through his lawyer, Sam Teppett, to a charge of dangerous driving causing injury.

In a statement, the 19-year-old said he always intended to admit his actions as he is "genuinely regretful" that they caused the accident.

"I am especially regretful for the harm caused to my good friend who was in the car with me. I am grateful that we both survived and have the opportunity to make something of the lives we have ahead of us, despite the fact that I have a bit of recovery still ahead.

"Not everyone is that fortunate. I have learned to appreciate life a lot more and to be grateful for what I have," the actor said in a statement to media.

Court records show Rolleston was driving at a speed considered "dangerous to the public" and caused injury to Kaleb Maxwell on July 26, who was in the vehicle with Rolleston at the time.

Rolleston was taken to Waikato Hospital's Intensive Care Unit where he remained for nearly a month.

Maxwell was also seriously injured in the crash.

Rolleston said since the accident, alongside his rehabilitation he has been working in the community for youth recognition of the importance of road safety.

"My hope is that this work, and the coverage of my story, will get other young people to take care on the roads for their own benefit and that of their friends and family.

"Just cause we are young, we are not indestructible, and in one stupid moment, there can be huge damage. I learned this the hard way but thankfully have a second chance.

"We all need to recognise this, every time, and for every second we are in a vehicle. I am grateful to my family, friends and the wider community for the incredible ongoing support that I have received.

"A part of me feels that I don't deserve it after letting everyone down by my act of stupidity that night.

"However, I have learnt and it is that understanding and support that strengthens my resolve to be the best I can be and to lead a positive, safe and responsible example for others in the future. I am grateful just to have the opportunity."

He was remanded at large until his sentencing at the Opotiki District Court on May 11.

The maximum penalties for a dangerous driving conviction are a $20,000 fine and five years in jail.