Emissions - On Board Diagnosis Monitor Readiness
NUMBER: 25-002-11GROUP: Emissions Control
DATE: December 02, 2011
SUBJECT:
On Board Diagnosis (OBD) Monitor Readiness
MODELS:
2010 - 2012 (DJ/D2) Ram Truck (2500/3500 Pick Up)
NOTE:
This bulletin applies to DJ/D2 vehicles equipped with a 6.7L Cummins engine (sales code ETJ).
DISCUSSION:
Vehicles that fail to pass a state mandated emissions inspection may have certain OBD readiness monitors that have NOT completely run. Anytime an ECM/PCM has been replaced or flashed, the OBD readiness monitors may need to run again to complete the monitoring process. This bulletin describes the necessary steps required to run each monitor.
Customers may be required to drive the vehicle for an extended period of time in a variety of driving styles to allow all of the OBD Monitors to run.
NOTE:
Using a generic scan tool is required to watch the monitors on the Cummins ECM/PCM. wiTECH scan tool does not display OBD monitors.
NOTE:
The names in brackets are the names that may be found on a generic scan tool.
1). Misfire Monitor [Misfire Monitoring];
The following conditions must be met:
^ Fuel level greater than 25 percent.
^ Battery voltage must be between 11 and 16 volts.
^ PTO or idle-up not engaged.
^ Final Aftertreatment Operating Mode is Normal.
^ Coolant temperature must be over 140 °F (60 °C).
To run the monitor:
- Allow the engine to idle for a minimum of 2 minutes.
- Vehicle must be stationary and/or not moving (Vehicle Speed = 0 MPH).
- Do not depress accelerator pedal (Accelerator Pedal Position = 0 %).
2). Fuel System Monitor [Fuel System Monitoring];
The following conditions must be met:
^ Fuel level greater than 25 percent.
^ Battery voltage must be between 11 and 16 volts.
^ PTO or idle-up not engaged.
^ Final Aftertreatment Operating Mode is Normal.
^ Coolant temperature must be over 140 °F (60 °C).
^ Grid heater is off.
To run the monitor:
- Let the vehicle idle for a minimum of 2 minutes with the above conditions met.
- Drive the vehicle at highway speeds. Perform a zero fueling event (Decelerate condition for 10 seconds, with foot off of accelerator pedal). Repeat 10-15 times.
3). Boost System Monitor [Secondary Air System Monitoring];
The following conditions must be met:
^ Engine must be running for 10 minutes.
^ VGT Compressor Inlet Air Temp must be below 122 °F (50 °C).
^ Mass Airflow must be above 2 kg/min.
^ Ambient Air Temperature must be above 20 °F (-7 °C).
^ Final Aftertreatment Operating Mode is Normal.
^ Coolant temperature must be over 140 °F (60 °C).
To run the monitor:
- Drive the vehicle on the highway. Perform a boost event (sudden depression of the accelerator pedal to provide turbocharger boost to the system). Repeat 15-20 times.
4). EGR System Monitor [EGR System Monitoring];
The following conditions must be met:
^ Coolant temperature must be over 140 °F (60 °C).
^ Final Aftertreatment Operating Mode is Normal.
To run the monitor:
- Drive the vehicle on the highway for 20-25 minutes.
5). Exhaust Gas Sensor (EGS) Monitor [02 Sensor Monitoring];
The following conditions must be met:
^ Engine must be running for 2 minutes.
^ Coolant temperature must be over 180 °F (80 °C) for more than 1 minute.
^ Final Aftertreatment Operating Mode is Normal.
To run the monitor:
- Drive the vehicle on the highway with the Final Aftertreatment Operating Mode in Normal Mode. Perform a zero fueling event (Decelerate condition for 10 seconds, with foot off of accelerator pedal). When accelerating gradually depress the accelerator pedal (Do not depress the accelerator pedal suddenly). Repeat 15-20 times.
- At the end of the drive at the dealership. Ensure the Exhaust Gas Temperature Sensor 2 is above 365 °F (180 °C). While the vehicle is in Park with the Parking Brake engaged, increase the engine speed to 1200-1300 RPMs for 2-3 minutes. Repeat this 2-4 times.
NOTE:
If the Exhaust Gas Sensor Monitor does not go to ready, key off the vehicle and allow for a 10 minute power down of the PCM before repeating the above directions.
6). NMHC System Monitor [Catalyst Monitoring];
The following conditions must be met:
^ Coolant temperature must be over 140 °F (60 °C).
^ Final Aftertreatment Operating Mode is DeSoot.
To run the monitor:
- Drive the vehicle on the highway for 12-15 minutes at steady state. After the 12-15 minutes of highway driving, exit the highway and proceed to a parking lot. Once in the parking lot come to a complete stop for 5 minutes. Repeat this if the truck is still in DeSoot.
7). Particulate Matter (PM) Filter System Monitor [Heated Catalyst Monitoring];
The following conditions must be met:
^ Exhaust Gas Temp Sensor 3 reading is above 150 °C (302 °F).
^ Inlet Air Pressure reading at idle is above 75 kPa (11 psi).
^ Soot Filter Delta Pressure reading is below 200 kPa (29 psi).
^ Coolant temperature must be over 140 °F (60 °C).
To run the monitor:
- This monitor requires a minimum of two DeSoots to complete the diagnostics.
- Drive the vehicle on the highway until the truck goes into DeSoot and continue to drive on the highway for 45 minutes. The truck will then need to complete a second DeSoot. Once the Second DeSoot completes, drive the truck for 15 minutes. The DeSoots do not need to be completed in the same drive cycle.
NOTE:
City driving or a stop and go driving style generally produces more soot and will enable the truck to achieve soot levels in the DPF that require a DeSoot the quickest.
8). NOx Aftertreatment System Monitor [02 Sensor Heater Monitoring];
The following conditions must be met:
^ Exhaust Gas Temp Sensor 3 reading is above 150 °C (302 °F).
^ Coolant temperature must be over 140 °F (60 °C).
To run the monitor:
- The vehicle will need to be driven on the highway until a DeSoot has been completed. Immediately following the DeSoot, the vehicle will go through some DeNox and DeSox events (~5 minutes). Once these are complete continue to drive on the highway at a steady speed until 10-15 DeNox events occur.
9). Comprehensive Component Monitor (CCM) [Comprehensive Component Monitoring];
To run the monitor:
- This monitor runs almost immediately at engine start. If it does not run, completely power down and restart the truck.
POLICY:
Information Only
Disclaimer:
This bulletin is supplied as technical information only and is not an authorization for repair.