DME 7.8 DME 7.8 0 · A - Oxygen sensor, bank 1

DME 7.8 DME 7.8 0 A - Oxygen sensor, bank 1 B - Oxygen sensor, bank 2 1 - Select system test. 2 - Select ’Request large lift’. If "Valve 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. 4 - Perform acceleration with wide-open throttle in 2nd gear, until "Valve lift diagnosis complete" appears. 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. ♦If misfires are stored, see Troubleshooting misfires. Perform system test for small lift Warning! During the system test for small lift, the valves remain at small lift, regardless of the type of driving. Faulty switching conditions can be detected by rough running, just like with misfire detection. If a valve is not switched to small lift, the fault type ’under limit’ is recorded. Several cylinders may be stored as faulty, although only 1 valve on one cylinder is faulty. In order to guarantee safety during repairs, the flat-base tappets of the inlet valves of the entire cylinder bank should be replaced if a fault occurs. A faulty flat-base tappet can be detected because the oxygen sen- sor FR for this cylinder bank enriches the mixture (FR > 1) during 1555 P1356 0-162 page 7 Printed in Germany, 2000 p1356