Method for testing a signal path

A method for testing a signal path of a first housed IC that forms a monolithically integrated circuit on a semi-conductor body together with a magnetic field sensor and has a signal output and a power supply connection and a test mode state and a normal operating state, wherein, during a normal operating state, an output signal is provided at the signal output, the output signal being dependent on a signal which is tapped at the magnetic field sensor, and a second housed IC is provided that is formed as a control unit, wherein via the control unit, a switch from the normal operating states to a test mode state is performed, the method comprising:

• switching off, in a first step, the power supply of the first IC;
• connecting, in a second step, the signal output with a reference potential;
• switching on, in a third step, the power supply of the first IC;
• disconnecting, in a fourth step, the signal output from the reference potential;
• and
• performing, subsequently in the test mode state, a self-test in the first IC and a test pattern is configured at the signal output or at the power supply connection and the test pattern is evaluated by the control unit for testing of the signal path.