The power semiconductor module comprises several semiconductor components, located on a substrate. A headrest stay element provided to the horizontal top portion is slidable vertically on a seat back. At least two indicators are in signal communication with the at least one sensor when the filter housing is mounted onto the manifold assembly. The two estimates are compared, and if they differ by more than a predetermined amount, sensor drift is diagnosed, and corrected. A disc drive that records data on a recording medium having a management area and data area records the support information in the management area.