Live data from diagnosis and egt sensor problem

Exp21

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Your Mercedes
s204 C200 CDI Blue Efficiency MY2012, w245 B200 CDI Facelift
Hi eveyone. I made a thread about an egt sensor error on my w245 euro5 CDI (https://forums.mercedesclub.org.uk/index.php?threads/b16-14-exhaust-temp-sensor.184523/#post-1859454). I have a problem: in the meantime that I was waiting for the new sensor to come, the check engine light turned off by herself. Today, noticing that the car was repeatedly trying to make a dpf regen I connected my Autel diagnosis and I observed live all the egt sensors values. I found:

- B16/14 (suspected faulty egt sensor) 100° C
- B19/11 (sensor upstream turbine) 650° C
- B19/8 (sensor downstream KAT) 714° C
- B19/9 (sensor upstream DPF) 608 °C

This is only an instantaneous. Values were constantly changing up to about 730° C. But the B16/14 was always around 100° C, even on full gas and engine load. Considering the position of this sensor (is half way between exhaust manifold and egr valve), do I have to think sensor is damaged? Why did the error turn off by himself if the sensor is still giving abnormal values? I don't understand. If I check all the values with engine turned off from 4 hours I find the B16/14 around 65° C (which is strange because coolant is 35° C and is the only hot part in the engine).
I think the sensor gives high values when cold and low values when hot. Do I have to replace it or the value of about 100° C during a regen is normal? Thank you!
 
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