GF49.10-P-3033AM Monitoring Catalytic Converter Efficiency, Function

GF49.10-P-3033AM Monitoring Catalytic Converter Efficiency, Function
ENGINE 113.990 in MODEL 211, 219
ENGINE 113.991 in MODEL 215, 220
ENGINE 113.992 in MODEL 230 up to Model Year 2008 /AEJ 07
ENGINE 113.993 in MODEL 463 up to 31.5.12
ENGINE 113.995 in MODEL 230 up to Model Year 2008 /AEJ 07





1 Amplitude O2
Sensor signal upstream of TWC
2 Amplitude O2
Sensor signal downstream of TWC
157 Firewall catalytic converter
158 Underfloor catalytic converter
A1 Instrument cluster
A1e26 "CHECK ENGINE" indicator lamp (for (USA))
A1e58 Engine diagnosis indicator lamp (except (USA))
G3/3 Left O2 sensor upstream of TWC
G3/4 Right O2 sensor upstream of TWC
G3/5 Left O2 sensor downstream of TWC
G3/6 Right O2 sensor downstream of TWC
N3/10 ME-SFI [ME] control unit
X11/4 Data link connector
CAN CAN data bus (Controller Area Network)

The firewall catalytic converters are assessed concerning their capacity to store oxygen. When the firewall catalytic converters are at operating state temperature and the lambda control has been enabled, the amplitude of O2 sensor signals downstream of the firewall catalytic converters are compared with the O2 sensor signal upstream of the firewall catalytic converters.
Changes in the oxygen content downstream of the firewall catalytic converters are almost completely dampened by the high oxygen storage capacity of the firewall catalytic converters.
This results in the O2 sensor signal downstream of the firewall catalytic converters being virtually constant (small amplitude).

If the firewall catalytic converter is no longer operational, the O2 sensor signal upstream and downstream of the firewall catalytic converters will be equal.
Several measurements must be performed in the specified engine speed and load range. The results are compared with a performance map from the ME-SFI [ME] control unit and recognized error are stored in the fault memory.

If a fault is detected, the engine diagnosis indicator lamp or (USA) the "CHECK ENGINE" indicator lamp is lit on the instrument cluster.

The stored faults can be read out and deleted with STAR DIAGNOSIS.