Can you provide more information about the M138-CCD error code and the specific machine or system that is generating it? Without additional context, it can be difficult to provide a specific or helpful answer to your question. However, generally speaking, the M138-CCD error code is related to
M138-CCD reads the PLC Marker point photo request signal timeout (D206=1) indicates that the marker point photo request did not receive a response from the PLC. This could be due to communication issues