A device includes an energy storage device, a plurality of electrodes, a memory, a switching circuit, and a processing module. The energy storage device stores electrical energy for delivery of defibrillation therapy to a heart. The memory stores N therapy configurations that define which of the plurality of electrodes are used to deliver defibrillation therapy and a waveform to be applied during delivery of defibrillation therapy. The switching circuit connects the plurality of electrodes to the energy storage device. The processing module controls the switching circuit to deliver defibrillation therapy according to a first therapy configuration of the N therapy configurations, detects a short circuit fault during delivery of the defibrillation therapy according to the first therapy configuration, and selects a second therapy configuration of the N therapy configurations based on when the short circuit fault was detected during delivery of the defibrillation therapy according to the first therapy configuration.