Preconditions for the test:
Engine idling.
No faults stored.
Engine temperature above 60 °C.
Induction air temperature below 60 °C.
All electrical loads switched off.
Gear selector set to ”P/N”.
Note:
For diagnosis of the catalytic converter.
The diagnosis takes about 100 seconds. If no result is obtained after 150 seconds, change the engine speed within the tolerance range.
Procedure:
Choose the function: Catalytic converter diagnosis.
Increase the engine speed to 2800-3200 rpm until the diagnostic status field changes from ”Test off” to ”Test on”.
The temperature of the catalytic converter must be above 352 °C.
Read the oscillation curve of the catalytic converter. Prescribed value max. 0.55.
Maintain the engine speed until the diagnostic status field changes from ”Test on” to ”Cat B1 OK! / Cat B1 not OK!”.