Description of Counters

COUNTERS, DESCRIPTION

Counter
A useful fault-tracing tool is the Diagnostic Trouble Code (DTC) counter. The control module stores 6 different counters for each Diagnostic Trouble Code (DTC), which describes the occurrence. The counters can be used to determine when and how often a fault has been detected. Using the counters for the Diagnostic Trouble Code (DTC) it is possible to see if the fault has only been registered during the current operating cycle or whether it has been detected previously.

If a fault is intermittent it is possible to determine how intermittent the fault is by studying the values of the different counters.

Example:
- Counter 1 = 15 Counts the number of operating cycles since the fault was last validated.
- Counter 3 = 69 Counts the number of operating cycles since the fault was first validated.
- Counter 4 = 1 Counts how many times the fault has occurred since the first time the fault was first validated.
- Counter 5 = 91764 The counter adds the time in seconds for which the control module has been operating since the fault was first validated and the diagnostic trouble code (DTC) was stored.
- Counter 6 = 0 The counter adds the time in seconds for which the test, the diagnostic, has run since the fault was first validated and the diagnostic trouble code (DTC) was stored.
- Counter 7 = 0 The counter adds the time in seconds for which the fault has been validated since the fault was first validated and the diagnostic trouble code (DTC) was stored.

In the examples given above, counter 1 gives the number of operating cycles where the diagnostic was run without a fault being detected. Counting takes place from when the fault was last detected. Counter 3 is the total number of operating cycles regardless of whether the diagnostic was run or not. Counter 4 shows the number of operating cycles where the diagnostic detected a fault. Counters 3 and 4 start to count from the first operating cycle after the operating cycle when the fault was first detected.

In the example, counter 4 = 1, which means that the fault was detected twice. One can see that no fault was detected during the relevant operating cycle. Depending on the number of operating cycles and the customer1s driving pattern, it can assist in ruling out this control module from the customer's current problems. The counters can help us understand how intermittent the fault can be. If the counters 1 = 0, 3 = 0 and 4 = 0 it indicates that there have not been any operating cycles since the fault was detected and that the fault was probably generated in the workshop.

For an operating cycle to be recognized certain requirements may be necessary, for example, increasing the engine coolant temperature. In certain cases ignition on, ignition off and ignition on again are counted as an operating cycle.

Counter 5 can be useful if the fault was detected in this operating cycle. The time can be used to determine more exactly when the fault occurred.

NOTE: Not all counters need be implemented in a control module, this varies from system to system. The possible counters are described below.

Counters, Description:

Graphs: