AFTERTREARMENT
*Important Note-Before starting the diagnosis process, verify that the ECM calibration is up to date. An outdated ECM calibration can lead to issues with sensors and modules.
1. Inspect the aftertreatment diesel exhaust fluid (DEF) in the tank for contamination. If contamination is present, replace the DEF in the tank.
2. Check for leaks starting at the turbocharger outlet and continue along the exhaust pipe to the aftertreatment diesel oxidation catalyst (DOC). Also inspect the exhaust manifold. Repair any leaks found.
3. Inspect the DEF system components for leaks, including the doser, DEF lines, and pump. Repair any leaks found.
4. Remove the doser and perform a DEF doser pump test. Ensure the spray is even, with no small or large droplets. If uneven spraying occurs, clean the doser and retest. If the problem persists, the doser may need to be replaced.
5. Perform the Aftertreatment SCR Test. If the test fails to complete, remove and clean the decomposition tube (the tube where the doser is mounted). If the test still fails, there may be an issue with the SCR system. If the test indicates a problem with the NOx sensor, replace the sensor.
TROUBLESHOOTING SHACK 