PC modules for InFocus displays use a special 80-pin connector. This connector supplies the PC with power and all connections to the display. This connector is always supplying some level of power.
Before removing or inserting a PC module, always disengage main power to the display via the main power switch or disconnecting the main power cable. As long as power is flowing to the 80-pin connector, it remains possible for that power to cause a short circuit during removal or insertion. This can permanently disable the 80-pin connector and other components in the PC module, for which there is no repair available.