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Multiplex Communication

SYSTEM DESCRIPTION

1. MULTIPLEX COMMUNICATION SYSTEM (BEAN)
a. The BEAN communication line is used for the body, meters and air conditioning controls. Since the line is loop-shaped, the communication can be kept by the line that is not open even if a part of the line becomes open for some reasons. In case that the line becomes short (bus-down) for some reasons, however, all the BEAN communication will be impossible and some DTC will be output.

HINT: When a bus-down occurs, the communication from the related ECU will stop. Therefore, an outputs of a DTC will be impossible. So, perform a DTC (SAE code) inspection with the intelligent tester.