PUMP GP-FUEL INJECTION 2092785 - Caterpillar

Table 1
J1939 Code and Description CDL Code and Description Comments
3217-16
Aftertreatment #1 Intake 02 : High - moderate severity (2) E1407 (2)
High Aftertreatment #1 Outlet 02 Concentration The Engine Out NOx Sensor is reading a higher than expected level of Oxygen (O2).
3227-16
Aftertreatment #1 Outlet 02 : High - moderate severity (2) E1408 (2)
High Aftertreatment #1 Intake 02 Concentration The Tailpipe Out NOx Sensor is reading a higher than expected level of Oxygen (O2). The exhaust system is equipped with two sensors that measure Oxides of Nitrogen (NOx) and Oxygen (O2). Sensor #1 is mounted in the exhaust pipe between the engine turbocharger and the Clean Emissions Module (CEM) and is referred to as the Engine Out NOx sensor. This sensor monitors the NOx and O2 coming out of the engine. Sensor #2 is mounted in the exhaust pipe after the Selective Catalyst Reduction (SCR) catalyst and is referred to as the Tailpipe Out NOx sensor. This sensor monitors the NOx and O2 exiting the SCR cannister.Follow the troubleshooting procedure in order to identify the root cause of the problem.
Table 2
Troubleshooting Test Steps Values Results
1. Check if NOx Sensors are Installed Correctly
A. Locate the appropriate NOx Sensor.
B. Check if the sensor is installed properly.
Properly Installed / Not Installed Properly
Result: The sensor is not installed properly.
Repair: Install the sensor properly. Refer to Special Instruction, REHS8151.
Proceed to Test Step 3.
Result: The sensor is installed properly.
Proceed to Test Step 2.
2. Check for Exhaust Leaks
A. Start the engine.
B. Check the exhaust system for proper installation.
C. Check for loose or broken exhaust joints.
D. Inspect the exhaust system between the turbocharger outlet and the tailpipe outlet for signs of an exhaust leak.
Exhaust Leaks
Result: An exhaust leak was found.
Repair: Repair or replace the component causing the exhaust leak.
Proceed to Test Step 3.
Result: An exhaust leak was not found.
Proceed to Test Step 3.
3. Replace the Failed NOx Sensor
A. Turn the DC breaker to the OFF position.
B. Replace the failed NOx sensor
NOx Sensor
Result: NOx Sensor was replaced.
If the problem is not resolved, proceed to Test Step 4.
4. Operate the Engine
A. Start the engine.
B. Connect Cat® ET.
C. Run the engine until normal operating temperature is reached.
D. Monitor the fault codes using Cat ET.
Fault Codes
Result: No codes are present.
Return to Service.
Result: A high oxygen concentration code is active.
Repair: Replace the failed NOx Sensor.
Verify that the repair eliminated the problem.
If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).