New check engine light problem

[ckkoch09]

Hi all, I got my truck back from having a bad plug on my def pump replaced last Thursday, made it until today and the engine light came back on. The new engine code is uo59f, has any one dealt with this one? It says it's a generic code for nox sensor b. I hear my def system working so I have to think this is not related. The truck is a 2014 ram 3500 with about 38k on it. The plug replacement was not covered under warranty as they said I damaged it by hitting it on something, who knows?? Just wondering if I should try something before I take it back in. At least this time the truck is running ok and is not counting down to a 5mph max speed.

Thanks for any input

 

[sag2]

This might at least pin down what sensor you need to look at in the diagnostic. So if the fault is always active it looks like two new sensors and modules. FYI, the connector at the module looks like it can be disconnected. Many guys have tried the first time and then learned the hard way when you have to replace the assembly.

Discussion: There has been confusion in the field regarding NOx sensor DTCs due to the differences in nomenclature between the scan tool, service information, and the parts catalog. The following information is being provided to help clear up the confusion as well as provide some additional checks to perform when dealing with these DTCs.
The following DTCs all pertain to the Downstream NOx sensor located in the outlet side of the SCR Catalyst. The downstream sensor may also be referred to as the System Out NOx sensor, NOX B, Lower NOx, Bank 1 Sensor 2, NOx Sensor 1/2 or Post Catalytic Reduction NOx sensor.
 P229F –NOx Sensor Circuit – Bank 1 Sensor 2
 P225E –NOx Sensor 1/2 Performance – Signal Stuck high
 P225F –NOx Sensor Circuit 1/2 Performance – Signal Stuck Low
 P22A7 –NOx Sensor Heater Circuit Performance – Bank 1 Sensor 2
 U059F –Invalid Data Received From NOx Sensor “B”
 P220B –NOx Sensor 1 Heater Sense Circuit Performance
 P1C56 –NOx Sensor Intermittent – Bank 1 Sensor 2
 P22FC –NOx Sensor Performance – Slow Response L


Theory of Operation

The aftertreatment system is equipped with two Nox Sensors and modules. The upstream NOx Sensor 1/1 is located before the SCR Catalyst and is permanently connected to a corresponding Nox Sensor Module mounted on the right frame rail. The downstream NOx Sensor 1/2 is located at the outlet of the SCR Catalyst and is permanently connected to a corresponding Nox Sensor Module also mounted on the right frame rail. The NOx Sensors and NOx Sensor Modules are calibrated to each other and must be replaced as an assembly. The two NOx Sensor and Module asemblies are not interchangeable. The NOx Sensor Modules are smart devices and communicate with the Powertrain Control Module (PCM) over the J1939 Data Link. The NOx Sensor Modules perform their own internal diagnostics and report malfunctions back to the PCM. The NOx Sensors are used to monitor the efficiency of the SCR Catalyst. The PCM will illuminate the MIL lamp immediately after the monitor runs and fails. The PCM will turn off the MIL Lamp after the monitor runs and passes for three consecutive trips.

• When Monitored: This monitor runs when the change rates of exhaust gas oxygen, NOx, exhaust pressure and exhaust flow are less than a calibrated threshold.
• Set Condition: Fault is set if the percentage of time we get the not valid bit is above a calibrated threshold within a fixed time frame.

[TABLE="width: 100%, align: center"]

Possible Causes



NOx SENSOR 1/2

[/TABLE]

 

[Bob4x4]

Did they flash your pcm?There are multiple choices that can be chosen on your model/year.[h=3]Theory of Operation[/h]The aftertreatment system is equipped with two Nox Sensors and modules. The upstream NOx Sensor 1/1 is located before the SCR Catalyst and is permanently connected to a corresponding Nox Sensor Module mounted on the right frame rail. The downstream NOx Sensor 1/2 is located at the outlet of the SCR Catalyst and is permanently connected to a corresponding Nox Sensor Module also mounted on the right frame rail. The NOx Sensors and NOx Sensor Modules are calibrated to each other and must be replaced as an assembly. The two NOx Sensor and Module asemblies are not interchangeable. The NOx Sensor Modules are smart devices and communicate with the Powertrain Control Module (PCM) over the J1939 Data Link. The NOx Sensor Modules perform their own internal diagnostics and report malfunctions back to the PCM. The NOx Sensors are used to monitor the efficiency of the SCR Catalyst. The PCM will illuminate the MIL lamp immediately after the monitor runs and fails. The PCM will turn off the MIL Lamp after the monitor runs and passes for three consecutive trips.

Your truck should not have a nox 1/2 and should have an scr cat that will not accept the ammonia sensor

 

[ckkoch09]

Thanks everyone for the input, I don't think they have flashed or have done any updates. They tell me the pcm is up to date. The only common thing that they seem to say is re-set the code and see if problem comes back. This is what they did the last time they worked on it and I only made a few blocks before the problem came back. I guess we will see what the dealership does on this one as they said this is a new problem. Thanks again for the VERY detailed information.