Home › Volvo › 2008 › XC90 Base, AWD › Repair and Diagnosis › Transmission › Automatic Trans › Transmission Control Module (TCM) Diagnostic Trouble Codes - 8 Of 9 › TCM-P086087: Transmission Control Module A Communication Circuit. Bus/Message Error. Message Missing (TF-80SC AWD; 2005) › Fault Tracing TCM-P086087