ENGINE AR-PRIMARY 3781549 - Caterpillar

Corrected 3516-2 Aftertreatment #1 DEF Concentration : Erratic, Intermittent, or Incorrect Trip Counter to Eliminate False Trips.
An estimated DEF level strategy was added to software to account for the DEF header with DEF quality sensor changing the DEF level reporting. When take is less than 10% or been drained empty would initiate trip fail to prime or loss of prime codes instead of low DEF level events. The fix will require that very quickly after ECM power-up, based on the raw sensor value. A Level 3 low DEF level code will be implemented when no DEF level value available from sensor while engine is running AND and later tank is drained while engine is running software will look for DEF pressure conditions to recognize failure.Fixes
Hot Shutdown Factory Password
Issue
A hot shutdown event drives a level three code causing factory passwords to clear it. This cause long down time for customersResolution
Changed hot shutdown under certain circumstance to be a level 1 which requires no factory passwords.High DEF Pressure Fault During Prime
Issue
False tripping of the 4334-16 Aftertreatment #1 DEF #1 Pressure (absolute) : High - moderate severity (2).Resolution
Updated to eliminate the false trips.DEF Tank and Coolant Temperature Kick Out
Issue
During the Aftertreatment function test, the test immediately aborts if conditions are not meet.Resolution
Changed the initiate requirements to allow preconditions of the coolant temperature to meet the DEF conditions. If DEF conditions are not meet, the Aftertreatment function test will abort.Cat Regeneration System (CRS) Nozzle Heater
Issue
The CRS nozzle heater shorten cycle was causing heater nozzle plugging.Resolution
The CRS nozzle heater timer resets and timer durations have been updated to correct this issue.Post Regen Main Fuel Spritz
Issue
A popping sound is noticed during post regeneration main fuel spritz.Resolution
Spark has been disabled during main fuel spritz action.Maintenance Timer (MTB)
Issue
Forced MTB regens with auto regen capability disabled on application are unable to reset the regen trigger request. This is leading subsequent regen requests without trigger getting reset. This can lead to operator confusion in the field.Resolution
Logic updated to go from MTB to Non-MTB at the end of the regen this will allow reset.Low Battery Voltage Diagnostic
Issue
False trip of the battery diagnostic during operator forced shutdown. This creates a derate without an active fault code.Resolution
The diagnostic was improved to reduce false tripping and derate issue.DPF #1 Intake Pressure Sensor Out of Calibration
Issue
False trip code 3464-13 DPF #1 Intake Pressure Sensor : Out of Calibration under cold ambient temperatureResolution
Changed the minimum DPF inlet temperature condition set point for the 3464-13 DPF #1 Intake Pressure Sensor : Out of Calibration.SCR Inducement DEF Control Unit Faults
Issue
The DCU faults were considered tampering faults which caused downtime and loss of productivity.Resolution
The DCU faults have been categories into tampering and non-tampering. This new change will trigger final inducement in 20 hours and is applicable for EPA regulation.NOx Sensor J1939 Datalink Faults
Issue
Logged a 5856-9 SAE J1939 Data Link #3 : Abnormal Update Rate.Resolution
Changed the ECM request for the NOx sensor reading to match J1939 requests.Fuel Pressure Sensor false trip
Issue
During sudden Engine Speed Drops or key cycle