At the moment, my Mercedes indy is confused about the following. Midway through July, I experienced the EML light coming on while driving on the highway. The code is P041B00, which means that the EGR temperature sensor 2 is malfunctioning. The engine is still running perfectly; the vehicle is a 2016 diesel with an OM626 Renault-based but Mercedes-EGR system. The mechanic tried cleaning the sensor connector and installing a new OEM sensor, but neither of these solutions worked. Finally, he decided to connect directly to the ECU, bypassing the wiring loom. However, while tidying up the new wiring, all four EGR sensors flashed as faulty, so he had to bypass the original wiring loom across the rear of the engine. Damaged wiring is a common problem in that area. Since the problem only happens on the highway, I went for a 30-minute drive to my dog walk and everything was fine on the way back. However, yesterday I went on a longer drive and the EML came back after 45 minutes with the same code; now he's wondering if the problem is due to a bad pin connection in the ECU! Everything was running well with the EGR system after it was cleaned in March, until this happened in July.
Even when the engine is completely hot, the fault does not occur when driving in urban areas.
Has anyone encountered this previously?
If the engine continues to run normally after you trace the sensor circuit from the EGR, that might be your only option.
Unsolved Mysteries!
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MercedesMan98
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Quite a few faulty ECU connections and even more faulty sensor connections have been my experience.
To the point where I no longer think the sensor is at fault.
To the point where I no longer think the sensor is at fault.
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MBcarOWNER
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I spent £141 on a sensor from MB, and it still hasn't fixed the problem.
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MercedesMan98
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Since the labour cost for investigating the wiring would probably surpass that, it is the logical first step.
Poor connections have made a lot of new, technologically complex cars unfeasible from a financial standpoint.
In addition to using pliers to squeeze the female connectors, I'm not sure how to guarantee a reliable restored connection or connections. You can't rely on electrical cleaning sprays. Are new covenants being squeezed?
Poor connections have made a lot of new, technologically complex cars unfeasible from a financial standpoint.
In addition to using pliers to squeeze the female connectors, I'm not sure how to guarantee a reliable restored connection or connections. You can't rely on electrical cleaning sprays. Are new covenants being squeezed?
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craigstomer
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using pliers to squeeze the female connectors...
Where exactly is that located? In MB WIS or on the "dark web". Please share
Where exactly is that located? In MB WIS or on the "dark web". Please share
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MercedesMan98
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Is that you being a little rude? 