Catalytic converter efficiency monitoring function - GF49.10-P-3033SM
ENGINE 113.986
ENGINE 113.987
ENGINE 113.988
ENGINE 113.989
The firewall catalytic converters (157) are assessed on their capacity to store oxygen. When the firewall catalytic converters are at their operating temperature and the lambda control has been enabled, the O2 sensor signals downstream of the firewall catalytic converter are compared with the O2 sensor signals upstream of the firewall catalytic converter (amplitudes).
Changes in the oxygen content downstream of the firewall catalytic converters are almost fully dampened by the high oxygen storage capacity of the firewall catalytic converters.
This means that the O2 sensor signals downstream of the firewall catalytic converters are almost constant (small amplitude).
If the firewall catalytic converters are no longer functional, the O2 sensor signals upstream and downstream of the firewall catalytic converters are equally large.
Several measurements must be performed within the specified engine speed and load range. The results are compared with a performance map by the ME control unit (N3/10) and faults detected are stored in the fault memory.
If fault detection occurs, the engine diagnosis indicator lamp (A1e58) lights up in the instrument cluster (A1) or for
the "CHECK ENGINE" MIL (A1e26).
The stored faults can be read out and deleted using STAR DIAGNOSIS.
| Component description for O2 sensors | G3/3, G3/4, G3/5, G3/6 | GF07.04-P-6100SM | ||
| Component description for the ME-SFI [ME] control unit | N3/10 | GF07.61-P-6000SM | ||
| Component description for the exhaust system | GF49.00-P-3010SM | |||
| Three-way catalyst, component description | 157, 158 | GF49.10-P-2010SM | ||
| Component description for the engine diagnosis indicator lamp | A1e58 | Except |
GF54.30-P-5010SM | |
| Component description for the "CHECK ENGINE" MIL | A1e26 | At |
GF54.30-P-5011SM |