Medium and Heavy Trucks
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Hi my name is***** with me while i pull up your code
5394 FMI 17
Data valid but below normal operating
Least severe level
Aftertreatment Diesel Exhaust Fluid (DEF) dosing amount too low or DEF quality
SCR catalyst malfunction
EGR mass flow failure
SCR inlet temperature
We can post back and forth as needed. The answer is the definition of the fault and the potential causes to trigger the fault. did you expect that the code definition would be different in my manual than other places on the web? I see you visually looked at the sensor and it was clean. That does not mean the sensor is good. It is possible the sensor is bad. Also which sensor are you referring to? Nox sensor? SCR inlet sensor? EGR mass flow? Did you inspect the catalyst for problems? Let me know
Do you have DDDL diagnostic software on a laptop?
If not there is no way of watching live data to see which sensors are not working properly so without doing that you will be buying these sensors hoping one will fix the problem and if not you might be finally replacing the catalyst and also possibly reflashing/updating the ECM software after.
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