We obtain the curvature form $F^ abla=Pcirc d^ ablacirc abla-d^ ablacirc Pcirc abla+d^ ablacirc ablacirc P$ for a vector bundle pseudoconnection $ abla$, where $d^ abla$ is the exterior derivative associated to $ abla$. We use $F^ abla$ to obtain the curvature of $ abla$. We also prove that $F^ abla=0$ is a necessary (but not sufficient) condition for $d^ abla$ to be a chain complex. Instead we prove that $F^ abla=0$ and $d^ ablacirc d^ ablacirc abla=0$ are necessary and sufficient conditions for $d^ abla$ to be a {em chain $2$-complex}, i.e., $d^ ablacirc d^ ablacirc d^ abla=0$.
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