1 - Select system test.
2 - Select 'Request small lift'.
If "Valve lift diagnosis not ready" appears, a fault may have been stored.
1. Erase the fault memory.
3 - Activate the system test with the key F8 immediately before acceleration with wide-open throttle.
The message "Drive link active" then appears.
NOTE: If 'Request small lift' appears, the valves remain at small lift, ie. the performance is reduced dramatically.
4 - Perform acceleration with wide-open throttle in 2nd gear, until "Valve lift diagnosis complete" (max. 4,000 rpm) appears.
At speeds above 4,000 rpm, misfires may be stored. Delete the fault memory and repeat the test.
NOTE:
- If a fault is detected, it is only recorded in the fault memory after 6,000 ignitions (at idling speed approx. 3 minutes waiting time).
- It is important to observe the oxygen sensor during acceleration with wide-open throttle or to record its behaviour with the data logger.
On Board Diagnostic
P0420
TWC Conversion, Bank 1 - Above Limit
Function
In order to assess TWC (three-way catalytic converter) conversion, the oxygen storage capacity of the TWC is determined by comparing the oxygen
sensor amplitudes after the TWC. If oxygen storage capacity is reduced due to ageing of the TWC, then the conversion of the TWC is also
diminished, and the amplitudes of the oxygen sensors after the TWC are increased.