Fault healing (CE light off)

When a fault occurs for the first time during a diagnostic routine, it is stored as a suspected fault. This suspicion is either confirmed (the fault occurs again) or refuted (the fault does not occur again, no display on a scan tool) in the subsequent driving cycle. If the fault activates the CE light, a fault healing counter that contains a certain value (e.g. 5) is started at the same time. During additional diagnostic routines, the fault healing counter will be decremented by 1 if the fault is not recognized in the same area window. When the fault healing counter has reached the value 0, the fault is considered to be healed. If the fault has triggered the Check Engine light, then the latter is switched off as long as this is not prevented by any other faults. The fault remains in the fault memory for the time being; it is not deleted again until a certain number of warm-up cycles (defined in the fault erasing counter) are completed successfully (as workshop help, e.g. if the tank cap is not screwed on tightly for a short time).