The present invention relates to an ECG system, comprising an ECG apparatus (2) and a plurality of electrodes (V1-V6, LA, RA, RL, LL). Each of the electrodes is provided with a light source. Both the electrodes and the light sources are electrically connected to the ECG apparatus (2). The ECG apparatus (2) comprises a running light mode. This helps a user to check proper placement of the electrodes. Moreover, the present invention relates to a corresponding method.