[rkundrat]

Not a day into ownership, my 335d showed an SES light. Brought to the dealer:

DeNOX system function and SCR System efficiency. Performed prompted test plans, removed metering module and checked for soil and correct installation of exhaust swirl flap. Okay. Performed SCR efficiency test plan. Road tested vehicle for 30 minutes per test plan. Test results pass, SCR functioning fault free and conditioning fault free. Cleared faults.

40 miles after picking it up the light is back on, code 4D16. The above sounds like a whole lot of testing, but nothing actually "done" to the car to treat the cause... I'm scheduled to go back in tomorrow, any thoughts/advise?? Is there a way for me to determine what this codes means and the course of action to correct?

[GreekboyD]

You'll most likely have to replace your NOx sensors and/or the SCR metering module. My buddy had that code and all of the above were replaced.

Good to see that you have competent techs where diesels are concerned.

[stevers314]

Post nox sensor. If they avoid replacing it long enough, you can look forward to the "no start in 400 miles" message when it completely shits itself.

[rkundrat]

Dealer replaced post SCR NOx sensor. Wanted to take the car overnight to do long road test and see if light reilluminates... I opted to road test myself.