Described herein are embodiments related to holdup self-tests in memory sub-systems for power loss operations. A processing device receives a request to perform a holdup self-test to detect a defect in a holdup circuit that powers the processing device and a memory component in the event of power loss. The processing device identifies a memory location of memory that is available and, responsive to detection of a loss of power, performs a continuous sequence of write operations to the memory location using holdup energy until all of the holdup energy is expended. After reboot, the processing device determines a number of the write operations that were successfully completed in the memory location before all of the holdup energy was expended. The processing device determines whether the number satisfies a defect criterion. Responsive to the responsive to the number satisfying the defect criterion, the processing device reports the defect associated with the holdup circuit.