Adblue short to ground 203D17 2015 mercedes w212
My car shows that kind of fault code and check engine light came on. I have faced this same problem randomly before but now engine checklight have been already 1.5 months on.
Fault code what star gives is 203D17 adblue short to ground.
Level sensor shows 0 ml as adblue level.
i have already made troubleshooting and found out that if i disconnect the cable from the trunk and measure it shows values:
1. between signal and ground cable 650Kohm
2.between signal and plus cable 2.2 Megaohm
3.When i feed 12volts to sensor to pins it gives back weird readings, voltage measuring from signal and and ground shows then 0.025-0-050 volts and if i measure ohms when current is on ,this reading changes all the time jumping between 79Kohms to 400Kohms
Car works normally,it remains power and also it uses adblue like normally.
I just wondering if I would get somekind of knowledge what values working sensor gives from signal line.
i would like to test if i put somekind of trimmer resistor between these wires if i get that engine fault light off like that way.
This sensor is not same i guess what was in cars before 2015. there was three different resistors but according wiring diagram I see only one sensor in my car. My car with U77 code
Level sensor in the middle pins 13,12,11
Thank you in advance
Br,
Jussi
Last edited by jussi.v; Aug 11, 2021 at 05:52 AM.




In US those cars have a settlement, who gives them emission system modifications and following 4 years extended warranty on all related components.
That would make it warranty repair in US
You might repost your question in diesel section for more comments.
In US those cars have a settlement, who gives them emission system modifications and following 4 years extended warranty on all related components.
That would make it warranty repair in US
You might repost your question in diesel section for more comments.
Unfortunately I haven't come across much in terms of sensor output or circuit measurements in WIS. Its mostly how to remove/install, system function/descriptions and circuit diagrams. Xentry and DAS have the guided tests.


