We present a detailed analysis of the voltage dependence of dangling bond recombination in microcrystalline silicon p-i-n diodes observed in the forward dark current at room temperature by electrically detected magnetic resonance (EDMR). The EDMR response is numerically simulated with physically reasonable parameters that are well suited to fully describe the electronic behavior of the diodes. A sign reversal as observed for amorphous silicon diodes is predicted at high voltages. The basic mechanism causing the sign reversal is shown to be due to space charge. The high sensitivity of the EDMR response to various material parameters is demonstrated.