DME 7.8 DME 7.8 0 · ther diagnostic operations, if the fault is present

DME 7.8 DME 7.8 0 ther diagnostic operations, if the fault is present in the same range window the counter is decremented by 1. If the persistence coun- ter has the value 0, the fault is assessed as persistent and regis- tered accordingly. If provided for by the fault category, the CE lamp is also activated. Remedying faults (CE lamp OUT) When a fault occurs for the first time during a diagnostic routine, it is stored as a suspected fault. In the subsequent driving cycle, the suspicion is either confirmed (fault recurs) or cancelled (fault does not recur, no indication on a scan tool). If the fault activates the CE lamp, a fault correction counter is started at the same time with a certain value (e.g. 5). In the course of further diagnostic routines, if the fault is not present in the same range window the correction counter is decremented by 1. If the correction counter has the value 0, the fault is assessed as remedied. If the fault activated the Check Engine warning light, this will be switched off if not prevented by any further fault. The fault remains in the fault memory for the time being and is only deleted after a number of further warm-up cycles (defined in the fault deletion counter) (workshop assistance if for example the tank cap is temporarily not correctly screwed in). Fault deletion counter A separate deletion counter is run for every fault detected. It con- tains the specified number of GO checks until deletion of the corre- sponding fault from the fault memory. When a fault is first detected, the deletion counter is, for example, set to 80 (suspected fault). If a non-persistent fault is detected as remedied, the deletion coun- ter (only visible for the PST2) is set to 10 (workshop assistance if fault very sporadic). Whenever a persistent fault is detected (= CE lamp ON), the deletion counter is set to 40, for example. This value is retained until the fault is detected as having been remedied. The deletion counter is decremented by 1 after every warm-up cycle if the fault is non-persistent fault or detected as remedied. Con- firmed faults not detected as remedied are not decremented in the deletion counter. If the deletion counter reaches the value 0, the fault is deleted from the memory. Fault frequency counter This counter shows how often a fault has recurred since its first occurrence. If the frequency value is 1, the fault has only occurred 2470 INTRODUCTION 0-PEIN page 7 Printed in Germany – 14, 2003 PEIN2DME78