Systems and methods are disclosed for performing run-time tests on a non-volatile memory (“NVM”), such as flash memory. The run-time tests may be tests that are performed on the NVM while the NVM can be operated by an end user (as opposed to during a manufacturing phase). In some embodiments, a controller for the NVM may detect an error event that may be indicative of a systemic failure of a die of the NVM. The controller may then select one or more blocks in the die to test, which may be dies that are currently not being used to store user data. The controller may post process the results of the test to determine whether there is a systemic failure, such as a column failure, and may treat the systemic failure if there is one.