METHOD FOR SELF-DIAGNOSIS OF AN INSULATION RESISTANCE MEASUREMENT CIRCUIT

The invention relates to a method for self-diagnosing a circuit (22) for measuring the insulation resistance of a battery system, said circuit (22) comprising: a first switch (S1) which connects the anode of the battery system (12) to the ground via a first comparison resistor (RS) connected in series; and a second switch (S2) that connects the negative electrode of the battery system (12) to a ground line via a second comparison resistor (RS) connected in series. A current measurement is carried out on the closed first switch (S1) in order to obtain a measured first current (IG1) and a current measurement is carried out on the closed second switch (S2) in order to obtain a measured second current (IG2), only one of the two switches (S1, S2) being closed at all times, and only one of the two switches (S1, S2) being closed at all times. According to the invention, a setpoint current (It1, It2) through the switch (S1, S2) is calculated on the basis of the voltage (UP/UM) of the battery system (12) and the magni