After moderate gains at the start of the week, the Dax fell back on Tuesday morning.
After the first few minutes of trading, the German benchmark index was 0.26 percent lower at 15,532.95 points.
Economic data such as the brighter GfK consumer climate initially did not provide any significant impetus.
For a few days now, the Dax has been hovering in a narrow range between 15,500 and 15,700 points, after having slipped to almost 15,000 points at the beginning of last week.
The 50-day line for the medium-term trend, which represents a major hurdle for the Dax, is currently just under 15,700 points.
Even in the back rows of the stock exchanges, things initially went downhill on Tuesday.
The M-Dax of the medium-sized stock market values lost 0.57 percent to 35,072.52 points.
The situation was similar on the European stock exchanges, with the Euro Stoxx 50, the leading index in the Eurozone, last dropping 0.44 percent to 4147.35.
In addition to the sentiment data, the eyes of investors on this trading day are also focused on the upcoming speeches by leading central bankers such as Christine Lagarde, Head of the European Central Bank (ECB), and Jerome Powell, President of the US Federal Reserve.