We present a recent study of light charged Higgs boson ($H^-$) production at the Large Hadron electron Collider (LHeC). We study the charged current production process $e^- p \to \nu_e q H^-$, taking in account the decay channels $H^- \to b\bar{c}$ and $H^-\to \tau \bar{\nu}_\tau$. We analyse the process in the framework of the 2-Higgs Doublet Model Type-III (2HDM-III), assuming a four-zero texture in the Yukawa matrices and a general Higgs potential. We consider a variety of both reducible and irreducible backgrounds for the signals of the $H^-$ state. We show that the detection of a light charged Higgs boson is feasible, assuming for the LHeC standard energy and luminosity conditions.