A processing system configured for capacitive sensing comprises transmitter circuitry, a first internal diagnostic mechanism, and a determination module. The transmitter circuitry is configured to transmit during a first time period with a first transmitter path of a plurality of transmitter paths in an input device. Each transmitter path of the plurality of transmitter paths is configured for capacitive sensing. The first internal diagnostic mechanism comprises a selectable leakage path. The selectable leakage path is configured to be coupled with the transmitter circuitry. The determination module is configured to determine if a discontinuity exists within the first transmitter path based on a discharge rate for the first transmitter path. The discharge rate is acquired during a second time period via the selectable leakage path of the first internal diagnostic mechanism, wherein the second time period occurs after the first time period.