OBDII diagnostics
OBDII diagnostics |
Trip |
Starting the engine and then driving in such a way as all the components and functions covered by the OBDII diagnostics have been monitored.
Driving cycle |
Starting the engine.
Example of a trip |
The car is driven for at least 15 min. (without gear positions P, R or N being engaged) with varying loads and engine speeds. The speed should exceed 25 km/h for the greater part of the “trip” (15 min.).
When limp-home trouble codes are generated :
The CHECK ENGINE and CHECK GEARBOX warning lamps go on as soon as the component has been diagnosed.When trouble codes are generated that do not affect limp-home:
The CHECK ENGINE and CHECK GEARBOX warning lamps go on during the second driving cycle after the component has been diagnosed (the trouble code is generated during the first driving cycle while the component is being diagnosed, however).To turn off the CHECK ENGINE warning lamp without taking further measures, 4 driving cycles must be completed in succession during which the component is diagnosed. The fault must not be detected during any of these driving cycles.
The components have different diagnosis times for the TCM control module. This means that certain DTCs can be generated before the entire “trip” has been completed.
Example
A fault is detected in a solenoid (S1) after about 0.5 seconds, while a fault in the transmission fluid temperature sensor is first detected after 15 min.