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Hi McCoy, My name is***** will be glad to help. Bare with me while I pull up your code information
Hi McCoy, I am glad you responded.Yesterday I was very sick and for some reason your question got lost in the archives... My apologies for that. I will gather this info now if you still need the help
Fault Code: 1921PID: S324SPN: 3251FMI: 0/16LAMP: AmberSRT:
Aftertreatment Diesel Particulate Filter Differential Pressure - Data Valid but Above Normal Operational Range - Moderately Severe Level. The soot load of the aftertreatment diesel particulate filter has exceeded the recommended limits.
Engine protection derate.
The engine aftertreatment system monitors the soot load in the aftertreatment diesel particulate filter. Under normal operating conditions, the aftertreatment diesel particulate filter is self-cleaning, where soot is converted to carbon dioxide, nitrogen, and water. Under light load operating conditions, it can be necessary to perform a stationary regeneration of the aftertreatment diesel particulate filter. The soot load in the aftertreatment diesel particulate filter is estimated using the aftertreatment differential pressure sensor and the calculated soot output of the engine.
This fault code can be triggered if the application is not operating at a duty cycle high enough to actively regenerate the aftertreatment diesel particulate filter. This fault code indicates that the exhaust temperatures exiting the turbocharger are not high enough to actively regenerate the soot that is trapped in the aftertreatment diesel particulate filter. It may be necessary to increase the duty cycle of the application in order to prevent plugging of the aftertreatment diesel particulate filter.
Possible causes of this fault code include:
Try a parked regen to see if it will complete with out any other active faults
If not and a reset with insite will not correct this and no actual faults exist you will need to reflash and update the ECM software. Let me know
Are there any other faults?
I see you have two questions open for this?
3 1921 Flashing Amber Perform stationary regeneration procedure Engine protection derate
Thanks for the update. I understand. Experts arent employees of the site. Some have full time jobs or businesses and only log in as they are able. I help on here in between jobs as I am able. But to answer your question, software can cause an ECM not to reset a code after repairs have been made. since you have the other two codes, I will dig those up in case they are why you are getting the 1921 which is very likely
Possible causes of this fault include:
CODE REASON EFFECT
Fault Code: 3261PID: S254SPN: 4342FMI: 5/5LAMP: AmberSRT:
Aftertreatment Diesel Exhaust Fluid Line Heater 2 Circuit - Current Below Normal or Open Circuit. Open circuit or short circuit to ground detected in the diesel exhaust fluid line heater 2.
Diesel exhaust fluid line heater 2 will be disabled
Fault Code: 3651PID: S254SPN: 3031FMI: 18LAMP: AmberSRT:
Aftertreatment Diesel Exhaust Fluid Tank Temperature - Data Valid But Below Normal Operating Range - Moderately Severe Level. The diesel exhaust fluid tank temperature is unable to reach its set point.
Diesel exhaust fluid injection into the aftertreatment system is disabled
These two faults you just posted will have to be corrected before regen is allowed. Repair these first and then try a parked regen.
Then yes, If the repairs have been made but the ECM will not clear or allow regen, you will need to have the ECM software reflashed and updated. Then try a parked regen. As long as there are not active problems and the repairs are good, the regen should be successful.
What active code for a pressure sensor? Are there more codes? 1921, 3651, and 3261 are what I know about. What is the currently active code number? If all active code troubleshooting and repairs have been made and the ECM will not allow regen then yes, reflash the ECM but if you have an active fault that has not been repaired then reflashing will not help at all. It is only if you have confirmed all repairs on all active faults and ECM will not Regen.
Thats right.. I was thinking of an informational code for engine derate... Sorry about the confusion. I was getting interrupted here. What are the FMI numbers for the codes?
Depending on the FMI numbers it could indicate a faulty sensor or harness unless its data valid and then points to an actual plugged system and filter
New sensor, harness, and DPF cleaned properly with the proper equipment.... Then the only thing left is ECM and ACM software. See that the FMI numbers are first....
3241 or 3251?
SPN 3251/FMI 16 - EPA10
This diagnostic is typically Diesel Particulate Filter (DPF) Pressure Out of Range High.
This fault code sets when the DPF outlet pressure is greater than 30 kPa (4.2 psi) for more than 10 seconds.
This means that the DPF Outlet sensor is reading high due to a restriction in the exhaust or faulty sensor
Was it the outlet sensor you changed?
check for a restricted SCR catalist
3251 16 does without engine running? If so, go with the reflash
Pleasure to help.
If the Outlet sensor on the DPF and harness are good then the fault should not exist after key on and a reflash. Keep me posted. Please remember to rate my service as that is how the site credits the experts for their time helping on here.