Abstract: A vehicular telemetry apparatus, operable to initiate a telemetry processing operation in response to an aperiodic, nonrandom trigger signal cued by a sensed, operationally-variable vehicular condition. A trigger unit provides the trigger signal which in turn switches the telemetry apparatus from a resource-conserving idle state to a state in which a session is initiated, so that operationally salient variations in information on changes in vehicle sensor data are detected and processed.