Home >> Volvo >> 2004 >> XC70 >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control Module (ECM) Diagnostic Trouble Codes (XC) - 5 Of 9 >> ECM-6000: Air Conditioning (A/C) Relay Signal. Signal Missing. Permanent Fault (B5254T2; 2003-2004) >> Signal missing. Permanent fault