Abstract: The solar X-EUV(X rays-extreme ultraviolet) imaging telescope is a solar shortwave imaging instrument, which can be used to monitor the solar activities and predict space weather. The solar X-EUV imaging telescope operates in the 0.4~10 nm X-ray waveband and the 19.5 nm EUV wavelength, and it can provide the high resolving solar full-disk. The filter wheel is an important part of the solar X-EUV imaging telescope, which can expand the dynamic range of responses, redound to reconstruct the plasma parameters from which different solar activities can be analyzed. Low power consumption is one characteristic of the movement control of the filter wheel, which needs to satisfy the special requirement of space application. In addition, it is the emphasis to develop a method to maintain the accurate position of step motor. There are two types of PECM(photoelectric coding matrix) that can be used to detect positions. And then, one of the types is adopted which is realizable in practice. Furthermore, form the point of view of functional reliability, the failure mode analysis of PECM is performed and the correspondent solution is provided.