Abstract: This study investigated how the computer-assisted concept mapping learning strategy employed in the Troubleshooting Learning Environment (TLE) influenced novice troubleshooters diagnose faulty systems and repair. The pre- and post-test control group design was used in the study. The participants (N = 50) included troubleshooters who were enrolled at Mitsubishi motors (Thailand). Participants attended a 5 days learning course. The group taking part in the experiment attended the computer-assisted concept mapping whereas the control group attended the traditional learning. Each group consisted of 25 practitioners. Data collection tools consisted of multiple-choice troubleshooting tasks and participants’ concept maps. The results revealed that learning in the computer-assisted concept mapping group had a significant positive effect problem solving skill.