Diagnostic trouble codes (DTCs)
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Diagnostic trouble codes (DTCs) are stored in the control module if the climate control module (CCM) detects a fault. Every diagnostic trouble code (DTC) has a counter which records the number of cycles which have been "fault-free" since the diagnostic trouble code (DTC) was stored. A fault which is detected in each operating cycle is defined as permanent. A fault which is detected in one or more operating cycles (although not the present one) is defined as intermittent.
An operating cycle is the period from when the ignition was switched on, remained on for at least 10 seconds and was finally switched off for at least 10 seconds.