Systems, methods, and devices for protecting against effects of magnetic fields are provided. One implantable medical device includes a lead including a first conductor and a second conductor. The device further includes a generator including an electronic circuit, a metal housing that has a ground potential, and one or more switching devices. The switching devices, in a safekeeping configuration, are configured to disconnect the second conductor from the electronic circuit and to connect the second conductor to the ground potential of the metal housing. The first conductor is connected to the electronic circuit in the safekeeping configuration. The switching devices, in the safekeeping configuration, are configured to cause the second conductor to shield the first conductor from at least a portion of the effects of the magnetic field while the first conductor remains connected to the electronic circuit for use in performing a sensing operation and/or a stimulation operation.
