Diagnostic Test
- CHECK THE OPERATION OF EXHAUST TEMPERATURE SENSORS NOTE:
This DTC will change to stored immediately after the exhaust temperature drops below the limit and will likely be stored when it enters the shop. For this reason, the diagnostic procedure should be performed for both active and inactive DTCs.
NOTE:Repair any fuel, emissions, or DEF system component DTCs before continuing with this diagnostic procedure.
- CHECK THE EXHAUST TEMPERATURE SENSOR FOR A SHORT TO ANOTHER CIRCUIT NOTE:
Perform this test on the EGT Sensor that was reading more than 43°F above or below the others.
- Turn the ignition off.
- Disconnect the Powertrain Control Module (PCM) C2 harness connector.
- Measure the resistance between the EGT Sensor Signal circuit and all other circuits in the PCM C2 harness connector.
Was the resistance above 10k Ohms between the EGT Sensor Signal circuit and all other circuits in the PCM C2 harness connector?
Yes
- Replace the Exhaust Gas Temperature Sensor in accordance with the service information. Refer to SENSOR, EXHAUST TEMPERATURE, REMOVAL .
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Repair the short between the Exhaust Gas Temperature Sensor circuit and the circuit that measured below 10k Ohms.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- CHECK THE DIESEL EXHAUST FLUID
- Turn the ignition off.
- Collect a sample of diesel exhaust fluid from the system.
- Visually inspect the fluid for signs of contamination or debris.
- Test the quality of the DEF using the DEF/UREA Refractometer 94-F-OOK-108-456 available through Pentastar Service Equipment (PSE).NOTE:
The DEF should register approximately 32.5 percent using a refractometer.
- To test for hydrocarbons in the DEF tank use hydroscopic test paper (PSE part number. 223-44-863). The test strip come in contact with the DEF fluid in the tank in order to get a valid reading for hydrocarbons present in tank
- Remove the oil/hydrocarbon detection paper from packing, inspect for color consistency. If color is not consistent replace strip.
- Disconnect the DEF fill pipe from tank and try to get a sample or remove the DEF tank.
- Place the detection paper directly into the DEF fluid in the tank. If the light blue paper turns dark blue, oil or hydrocarbon contamination exist.
Is the diesel exhaust fluid quality within specification and free of debris and contamination?
Yes
- Go To 4
No
- Drain the diesel exhaust fluid from the tank and fill the system. If the fluid is contaminated, follow the cleaning procedure. Refer to TANK, DIESEL EXHAUST FLUID, CLEANING .
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- CHECK FOR CYLINDER MISFIRE
- Start the engine.
- With the scan tool, navigate to Systems Tests, and perform the Injector Kill system test.
Were any cylinders found to be faulty or low?
Yes
- Perform the CHECKING ENGINE MISFIRE / RUNS ROUGH / PERFORMANCE TEST diagnostic procedure. Refer to DIAGNOSIS AND TESTING, 6.7L .
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 5
- CHECK FOR EXCESSIVE ENGINE OIL BEING INTRODUCED INTO THE AFTERTREATMENT SYSTEM
- Turn the ignition off.
- Remove the turbocharger outlet and inspect for signs of oil, fuel or moisture being introduced into the aftertreatment system from the engine.
Was engine oil, fuel or moisture found in the turbocharger exhaust outlet?
Yes
- Locate the cause of possible diesel fuel or engine oil being carried from the engine into the exhaust system. Inspect the SCR Catalyst for possible damage.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 6
- CHECK THE DOC/DPF CATALYST FOR PLUGGING
- Remove the DOC/DPF Catalyst and check the inlet side for signs of soot accumulation or face plugging.
Does the DOC/DPF Catalyst show any evidence of face plugging or soot accumulation?
Yes
- If DTC P1451 is present, perform a scan tool initiated regeneration of the aftertreatment system.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- If DTC P1451 is not present, replace the DOC/DPF assembly in accordance with the service information. Refer to FILTER, DIESEL PARTICULATE, REMOVAL .
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- Remove the DOC/DPF Catalyst and check the inlet side for signs of soot accumulation or face plugging.