Diagnostic Trouble Codes (DTCs)

A diagnostic trouble code (DTC) is stored if the control module detects a fault. There are approximately 18 diagnostic trouble codes (DTCs) for standard carphones, approximately 25 for carphones with Volvo On Call / Volvo On Call Plus (USA). A fault which is detected in the most recent operating cycle is defined as permanent. Other faults which are detected are defined as intermittent.