The time-event hybrid-triggered output feedback control method for vehicle platoons was proposed in consideration of the unmeasurable partial state information and the balance between control performance and communication resources. For the unknown states of vehicles due to sensor cost and data acquisition accuracy, an observer that estimates the unknown velocity and acceleration from position was designed, achieving an arbitrarily small reconstruction error. A novel time-event hybrid-triggered mechanism was developed: the time-triggered mechanism was applied in a state fluctuation process to achieve the convergence of the tracking error, and the system switched to the event-triggered fashion in a steady state to reduce the communication resources. By employing the backstepping control technique, an output-feedback controller was devised to achieve platoon control using only position information. The stability of the proposed method and the avoidance of the Zeno phenomenon using the time-event hybrid-triggered mechanism were demonstrated through theoretical analysis. Simulation results under the extra urban driving cycle (EUDC) show that, compared with the single time/event-triggered mechanism, the proposed method maintains platoon control performance while significantly reducing communication resources.