An on-board recording system for a vehicle, wherein the on-board recording system is configured to monitor data for errors, the on-board recording system comprising: one or more processors; a memory, and a mass storage device comprising a database; wherein the memory is coupled to the one or more processors, and wherein the memory is adapted to store data and program code that, when executed by the one or more processors, is adapted to cause the on-board recording system to: receive as input a data sequence including a plurality of frames; wherein each frame includes a message and a label comprising at least one message identifier; wherein the message comprises data representing one or more operating parameters of the vehicle, and the label comprises message identifiers for each operating parameter; wherein each message identifier comprises a time offset; wherein each frame containing a particular message is repeatedly received and recorded by the on-board recording system at the end of every time period given by the value of the time offset of the message identifier corresponding to the particular message; the on-board recording system being characterized in that it is configured to: determine that one or more messages received at the corresponding time offset do not contain any data, whereby a time gap is created in the data sequence recorded and stored by the on-board recording system; calculate a total length of time where time gaps exist in the data stored in the memory of the on-board recording system; compare the total length of time with a threshold length of time; wherein if the total length of time is determined to be greater than the threshold length of time determine that a threshold-time error has occurred. one or more processors; a memory, and a mass storage device comprising a database; wherein the memory is coupled to the one or more processors, and wherein the memory is adapted to store data and program code that, when executed by the one or more processors, is adapted to cause the on-board recording system to: receive as input a data sequence including a plurality of frames; wherein each frame includes a message and a label comprising at least one message identifier; wherein the message comprises data representing one or more operating parameters of the vehicle, and the label comprises message identifiers for each operating parameter; wherein each message identifier comprises a time offset; wherein each frame containing a particular message is repeatedly received and recorded by the on-board recording system at the end of every time period given by the value of the time offset of the message identifier corresponding to the particular message; the on-board recording system being characterized in that it is configured to: determine that one or more messages received at the corresponding time offset do not contain any data, whereby a time gap is created in the data sequence recorded and stored by the on-board recording system; calculate a total length of time where time gaps exist in the data stored in the memory of the on-board recording system; compare the total length of time with a threshold length of time; wherein if the total length of time is determined to be greater than the threshold length of time determine that a threshold-time error has occurred. receive as input a data sequence including a plurality of frames; wherein each frame includes a message and a label comprising at least one message identifier; wherein the message comprises data representing one or more operating parameters of the vehicle, and the label comprises message identifiers for each operating parameter; wherein each message identifier comprises a time offset; wherein each frame containing a particular message is repeatedly received and recorded by the on-board recording system at the end of every time period given by the value of the time offset of the message identifier corresponding to the particular message; the on-board recording system being characterized in that it is configured to: determine that one or more messages received at the corresponding time offset do not contain any data, whereby a time gap is created in the data sequence recorded and stored by the on-board recording system; calculate a total length of time where time gaps exist in the data stored in the memory of the on-board recording system; compare the total length of time with a threshold length of time; wherein if the total length of time is determined to be greater than the threshold length of time determine that a threshold-time error has occurred. determine that one or more messages received at the corresponding time offset do not contain any data, whereby a time gap is created in the data sequence recorded and stored by the on-board recording system; calculate a total length of time where time gaps exist in the data stored in the memory of the on-board recording system; compare the total length of time with a threshold length of time; wherein if the total length of time is determined to be greater than the threshold length of time determine that a threshold-time error has occurred.