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System Communication

The communication between the 9 OSM modules, the BCM and the Left Switch Pod (LSP) is the duty of the data line circuits. The BCM continuously scans from the LSP to each of the 9 OSM modules, one at a time. As it is doing this, it is continuously making commands and requesting information from each component. See Fig 1.

The data line circuit is designed as a complete loop so that each element on the data line circuit has 2 data inputs. This loop design allows the circuit to work with one open in the circuit.

Fig 1: Lighting System Data Line Circuit
G00097079Courtesy of GENERAL MOTORS CORP.