Schettino Concordia trial
Captain Francesco Schettino asked judges in Grosseto to let him take part in a survey on board of the Costa ConcordiaReuters

Francesco Schettino, the captain of the cruise liner that ran aground off an Italian island two years ago, has been allowed to go back on board by a Tuscan court.

Judges in the city of Grosseto agreed to a request by lawyers for Schettino, who demanded that he takes part in a survey of the Costa Concordia later this week.

The request came as a team of lawyers and experts were due to inspect an emergency power unit on the 11th deck of the liner, which allegedly did not work on the night of the shipwreck in January 2012.

Meanwhile Grosseto prosecutors have opened a separate investigation into two employees of the Concordia's operator, Costa Crociere.

Costa Concordia guardian Franco Porcellacchia and Captain Camillo Casella have been indicted for allegedly entering the ship after it was sealed by police.

Thirty-two people died after the Concordia hit a rock off the island of Giglio, took on water and capsized.

Prosecutors said Schettino steered the liner too close to the island because he wanted to perform a sail-past salute.

Pilloried as "Captain Coward" in the Italian media, Schettino allegedly hesitated to raise the alarm and then abandoned the Concordia with hundreds of passengers still on board.

He faces up to 20 years in jail on charges of manslaughter, causing a shipwreck and abandoning ship. The captain is the sole defendant on trial and denies the charges.

Another five employees of Costa Crociere were granted plea bargain deals in return for milder sentencing in a separate proceeding.

The Concordia was set upright in an unprecedented salvage operation known as parbuckling in September last year.