Serial Communication Circuit
Memory and return command signals, and mutual communication during return operation, pass between the ECU and the tilt and telescopic ECU in the form of serial data communication. Signals activating memory and return operations are sent from the tilt and telescopic ECU to the ECU and mirror ECU. When the ECU receives a memory signal, its a position is memorized, and when a return signal is received, the position is returned to the memorized position. During return operation, tilt and telescopic ECU and ECU and ECU continue mutual communication constantly, and is a malfunction should occur in the communication wire, the tilt and telescopic ECU stops the signal output to ECU and stops return operation. However, the tilt and telescopic ECU continues return operation. Even with power return stopped, manual switch operation of the power seat is possible. The mirror ECU receives activation signals only and is not involved in reciprocal communication during return operation, so even when a reply signal from the ECU to the tilt and telescopic ECU is abnormal and the power seat stops return operation, the mirror ECU continues return operation. See Fig 1.