When a lensed quasar crosses the caustic network of the lens galaxy, the microlensing flux amplification generally varies with wavelength. This is a direct consequence of the wavelength dependence of the spatial distribution of the emission from the quasar. We demonstrate here X-ray light curves in several wave bands during the crossing for different accretion disk models, with an emphasis on the sensitivity to the model parameters. For these simulations we use fully relativistic disk models including Doppler shift, gravitational redshift and self-lensing by the central rotating black hole. In addition, we present simulations of the changing shape of the X-ray iron K-alpha line during the caustic crossing.