This diagnostic procedure supports the following DTC:

DTC B0040 No BCM Serial Data

With the ignition in either the Accessories position or the On position, DTC B0040 will set to indicate that the radio has not received any data from the BCM for more than 10 seconds. This does not necessarily mean the radio has a fault, it usually indicates that the radio has been in operation on a workbench and the bus has not been connected.