A biosensor has an abnormal output detection system that determines whether an output signal from the redox reaction of an analyte has a normal or abnormal shape or configuration. The abnormal output detection system improves the accuracy and precision of the biosensor in determining whether an output signal has a shape or configuration that may not provide an accurate and/or precise analysis of a biological fluid. The biosensor generates an output signal in response to the redox reaction of the analyte. The biosensor normalizes the output signal and compares the normalized output signal with one or more control limits. The biosensor may generate an error signal when the normalized output signal is not within the control limits.
