Proceedings at the Mannheim district court were cut short just after charges were read when Kachelmann's lawyers requested a discussion with judges, state prosecutors and the plaintiff's lawyers.
Meanwhile Kachelmann's former long-time girlfriend, who has accused the 52-year-old of threatening with a knife and raping her on February 9, reportedly said she no longer wanted to take part in the trial.
The latest hiccup in the case came after the district court turned down the defence request to have two lead judges removed on the first day of the trial last week due to doubts over their impartiality. The move had forced authorities to postpone the trial after just a few minutes, but on Friday it was announced that the two judges in question would remain as the trial resumed.
The Swiss-born weather expert and founder of Meteomedia weather service faces up to 15 years in prison if he is found guilty of charges he denies.
Some 25 witnesses have been called to testify before the court in the southwestern state of Baden-Württemberg, among them “various female witnesses from the circle around the accused” and five experts, according to prosecutors.
Kachelmann was arrested at the Frankfurt airport on March 20, 2010 and held on remand for four months until late July. A Mannheim court had said they had insufficient evidence to continue holding him.
A verdict in the trial is expected at the end of October.