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O2 sensor signal - fault code description ME - AD07.61-P-4000-06AA

    O2 sensors downstream of TWC (G3/5, G3/6), no sensor state change
1A Fault code P200E Right O2 sensor downstream of TWC (G3/6) (-)
(USA ONLY Readout on generic scan tool) P2081 Left O2 sensor downstream of TWC (G3/5) (-)
1B Engines 112, 113 as of 1/01 P200E-[1 ] Right O2 sensor downstream of TWC (G3/6), threshold exceeded (-)
Fault code
(USA ONLY Readout on generic scan tool)
P200E-[2] Right O2 sensor downstream of TWC (G3/6), threshold not reached (-)
P2081-[1] Left O2 sensor downstream of TWC (G3/5), threshold exceeded (-)
P2081-[2] Left O2 sensor downstream of TWC (G3/5), threshold not reached (-)
2 Fault storage
Actuation of the engine diagnosis indicator lamp (EURO3/4)
or CHECK ENGINE (MIL) malfunction indicator lamp USA ONLY
after expiry of test duration and fault
no actuation
3 Checking frequency Continuous
4 Checked signal or status Sensor state change
5 Fault setting conditions  A sensor state change must be recognized after about 190 seconds for a switched-on two-sensor control.
6 Check prerequisites
  • Engine speed approx. 750 to 2500 rpm
  • Load 20 to 60%
  • Diagnosis of O2 sensors upstream of TWC enabled
  • The fault "O2 sensor upstream of TWC aging, correction parameter exceeded" must be recognized on the assigned O2 sensor upstream of TWC.
  • Catalytic converter temperature greater than 350°C
  • No fault in O2 sensor heater.
7 IMPORTANT If the O2 sensor downstream of TWC is so defective that the sensor voltage remains slightly under the regulating threshold then the lambda control is enriched to a maximum over TV . Monitoring of the correction parameter for the O2 sensor upstream of TWC then wrongly recognizes a defective O2 sensor upstream of TWC.
In order to exclude such an error after the fault entry "O2 sensor upstream of TWC aging, correction parameter exceeded" has occurred the sensor signal of the O2 sensor downstream of TWC is checked for a sensor state change.
The O2 sensor downstream of TWC is to be replaced if no sensor state change is recognized.