Normal Operation

The Body Control Module B (BCM-B) monitors the drive select range and the brake lamp on messages from the Instrument Panel Cluster (IPC) over the Medium Speed Controller Area Network (MS-CAN), and if it does not receive a drive select range and the brake lamp on message in more than 5 seconds, the BCM-B  will set this DTC in continuous memory. The BCM-B  monitors the MS-CAN  for this information with a data sampling rate of once every 10 milliseconds.

• DTC U0155:87 (Lost Communication With Instrument Panel Cluster (IPC  ) Control Module: Missing Message) - set by the BCM-B  if data messages received from the IPC  over the MS-CAN are missing for longer than 5 seconds.
• DTC U0423:68 (Invalid Data Received from Instrument Panel Cluster Control Module: Event Information) - a continuous memory and on-demand DTC that sets when the BCM-B  does receive a drive select range message but does not receive a drive select status message for longer than 3 seconds with a data sampling rate of once every 10 milliseconds.

This pinpoint test is intended to diagnose the following: 

• Module communication
• BCM-B 
• IPC