In-vehicle communication system, in-vehicle relay apparatus, and in-vehicle control apparatus

An in-vehicle communication system, comprising:

• a first relay apparatus installed in a first area of a vehicle;
• a second relay apparatus installed in a second area of the vehicle, the second relay apparatus being connected to the first relay apparatus via a communication main line that runs into both the first area and the second area;
• a main control apparatus and an auxiliary control apparatus installed in the first area, the main control apparatus and the auxiliary control apparatus being connected to the first relay apparatus via a communication branch line and performing driving control of the vehicle;
• a controlled apparatus installed in the second area, the controlled apparatus being connected to the second relay apparatus via a communication branch line and being controlled by the main control apparatus or the auxiliary control apparatus;
• a first input apparatus installed in the first area, the first input apparatus inputting information used in the driving control to the main control apparatus or the auxiliary control apparatus;
• and
• a second input apparatus installed in the second area, the second input apparatus being connected to the second relay apparatus via a communication branch line and inputting information used in the driving control to the main control apparatus or the auxiliary control apparatus via the first relay apparatus and the second relay apparatus, wherein
• the first relay apparatus and the controlled apparatus communicate via an auxiliary communication line provided running into both the first area and the second area;
• in a case where communications via the communication main line are not possible, the main control apparatus and the auxiliary control apparatus communicate with the controlled apparatus via the auxiliary communication line;
• and
• in a case where the main control apparatus cannot control the controlled apparatus, the auxiliary control apparatus controls the controlled apparatus.