Operation CHARM: Car repair manuals for everyone.

Monitors, Trips, Drive Cycles and Readiness Codes






Driving cycle/operation cycle




All control modules' diagnostics require that some form of driving cycle or operation cycle is run for diagnostics to be considered as complete. The terms driving cycle or operation cycle appear, these mean the same, they are only different designations.
Example
The illustration above shows an example of a driving cycle or operation cycle. The vehicle is started and driven (Start), is stopped sometime and the ignition is turned off (Stop). When the ignition is turned on again (Start) a new driving cycle starts.
A new driving cycle or operation cycle usually starts every time the ignition is turned on, which means that you should turn on the ignition, turn off the ignition, and then turn on the ignition again.
However, the condition varies from control module to control module, there are also, e.g., speed and temperature conditions, before a driving cycle or operation cycle is considered to be complete.
When a malfunction is detected and then is confirmed as a real malfunction and is stored, various counters are also stored, indicating how frequent the malfunction is. These counters use driving cycles or operation cycles as basis for updating the counters' values.
For information on counters, see further on in the document.