Opel TID Display

Something new to report.
Using TID8 works fine, TID10 not. I have added some serial communication to observe the calls of the function. I am using this code:

void loop () {
  start = millis();
  start_tid();
  tid_address(0x9B);  //this is the address for the 8 letters, for the 10 use 0x9B instead
  tid_data(0);  //first symbols byte
  tid_data(0);  //second  symbols byte
  tid_data(0);
  
  tid_data('C');    //first letter
  tid_data('o');
  tid_data('r');
  tid_data('s');
  tid_data('a');
  tid_data(0);
  tid_data('C');
  tid_data(0);    //8th letter
  tid_data(0);
  tid_data(0);
  stop_tid();   
  
  end = millis();
  time = end - start;
  Serial.println(time);
}

Using this (with eight letters) with the TID8 gives about 50ms of duration, which works fine, the text is beeing displayed. With the TID10 it takes about 60ms, but the text appears only sporadical. I dont have any clue why or how to solve this.
I have no idea, what I can do further.