Home › Volvo › 2004 › S40 T-5, Standard › Repair and Diagnosis › Transmission › Automatic Trans › Transmission Control Module (TCM) Diagnostic Trouble Codes - 1 Of 2 (544 Body) › TCM-0A30: Control Module Communication. Signal Missing From Engine Control Module (ECM) (Aw55-50/51SN; 2004-11) › Fault-Tracing Information