An electronic torque wrench (10) comprises a body with an axial extension along a longitudinal axis (11), a front end provided with a coupling (14) intended to engage the wrench on a joint to be tightened by manual rotation around a rotation axis (15) which is transverse to the longitudinal axis (11), and a handle (13) along the body for operating the wrench. A sensor (16) is intended to detect a torque applied with the wrench to the coupling (14) and comprises two flex sensor elements (16a and 16b) which are arranged spaced apart along the longitudinal axis (11). An electronic control circuit (17) is connected to the sensor (16) for receiving signals from it and is intended to implement a method which comprises the steps: calculating, depending on flexing values detected by the two sensor elements (16a and 16b), the point P along the longitudinal axis (11) which is used for applying the manual force of rotation of the wrench about the rotation axis (15); comparing the position of the point P with admissible predefined positions along the longitudinal axis (11); and emitting an error signal if the position of the point P does not correspond to these admissible positions.