was it grey? If yes the cable already connected to the T is the cable going to the DAQ. That's why there is a T already. Don't disconnect any signals without checking in advance what they are and what they are used for. Some of them are required for locking, e.g. the transmitted light is required for the servo as a feedback if it is locked or not for the temp feedback. If you have to disconnect anything do it but put an entry in the elog.