The LAN tester PCE-LT 15 is a combination device which detects configuration errors in the network and at the same time can be used as a multimeter. Thus, the periphery of a network can be quickly checked with the LAN tester. With the LAN tester PCE-LT 15 it is possible to check 8-pin data cables with RJ-45 connectors for continuity, open connections, and short circuits. In addition to the LAN test function, the LAN Tester can also measure DC and AC voltages. With the LAN tester, which also serves as a multimeter, it is possible to perform a continuity test with buzzer and a diode test. The LAN tester is also a device that identifies the most common network installation errors. The two-row LEDs successively indicate the pin assignment of the cable to be tested. In the event of a short circuit, more than two LEDs light up simultaneously.