15304 - Service Update. This bulletin provides a service procedure to reprogram the transfer case control module on the vehicles listed above. In low ambient temperatures, below 5°F (-15°C) a transfer case brake motor assembly malfunction may occur. Diagnostic Trouble Code (C0398 - Range Position Correlation Fault) will be set, locking the transfer case in ?4HI? until the vehicle is serviced. This software update also addresses other transfer case control issues for overall improved drivability.