The software developed for automotive systems is usually extremely complex and consists of numerous software modules. Tools that enable the visualization of the complexity of program code must provide code architecture analysis and insight into potential errors, and thus increase the efficiency of programmers and software architects and ultimately save time and money. Existing solutions and manufactured tools are usually developed for a specific purpose and are often not sufficiently automated. They are subject to optimization and improvements because the software for which these tools are intended is becoming more complex, and thus the tools need to be upgraded. The tool presented in this paper is based on the data obtained from the program code documentation whose architecture has to be displayed and the data extracted from the generated map file. The program code documentation is made in JSON format, which is suitable for viewing in a web browser. Extraction of data from generated map files is done using the Python programming language and the pandas and difflib libraries. The visualization was created using the JavaScript programming language and the D3.js library, as well as using HTML and CCS. The tool allows parallel display of graphs describing the same program module in such a way that one graph is generated with the data from the documentation and the other one with data from the map file. Graph comparison is the most important functionality of this tool, and it shows the differences between the graph created from the documentation and the graph created from the map file. In this way, tool enables the detection of potential errors and it generates the corresponding report. The functionalities of the tool are shown in three examples that represent realistic scenarios possible when using this tool.