Hello, with my Smart 453 with 70ps. the engine warning light is displayed. I read this out, and then comes the error P2243 (at AutoDoctor) and P2244 at CarScanner. Both should however indicate a fault of the Lambda probe in front of the cat. If I look at the voltages of the two probes: Lambda 1 and Lambda 2 is then, Lambda 1 is constant at 1.28V and Lambda 2 without gas also at 1.28V but I give gas then it goes down and then up again. If I really miss it Then the probe before the cat should control the whole mixture, for that the voltage must then vary. And the probe after the cat should remain constant. If the after the cat fluctuates this should be a sign of a problem with the cat. So now I see the Lambda 2 regulated depending on the gas and Lambda 1 is constant. Is the Lambda 2 the probe before the cat? From the Logic I would have thought that the Lambda 1. Does someone know that? and if Lambda 2 is in front of the cat, and this now regulates, what exactly can the error be? If I delete the error it will come back even after more or less short time. Thanks already