Circuit Description

The body control module (BCM) sends serial data along the secondary serial data bus circuit. This is read by the instrument cluster to indicate the status of the various components on the serial data line. DTC 9 will set if there is no BCM data message on the bus for more than 10 seconds. In practice the trouble code is set somewhere between 10 and 20 seconds after the last BCM data message is received by the instrument cluster. The DTC is reset within 10 seconds of the arrival of a BCM data message on the bus. The DTC is logged as a History DTC.