P2459

P2459-DIESEL PARTICULATE FILTER REGENERATION TOO FREQUENT

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The engine after treatment system monitors the soot load in the Diesel Particulate Filter. Under normal operating conditions the Diesel Particulate Filter is self-cleaning, where soot is converted to ash. The soot load in the after treatment Diesel Particulate Filter is estimated using the Exhaust Differential Pressure Sensor and the calculated soot output of the engine. The Powertrain Control Module (PCM) will set this fault if it detects that the time between two regeneration events is less than the calibrated time threshold. The PCM will illuminate the MIL lamp immediately when the diagnostic runs and fails. The driver will be notified via the vehicle's EVIC Message Center. The PCM will turn off the MIL lamp immediately after the soot load has dropped below the Moderately Severe Level Threshold.

- When Monitored:
The diagnostic runs continuously when the engine is running.

- Set Condition:
If between two Diesel Particular Filter regeneration events, the DPF soot loading rate is faster than the threshold or if the time between two regeneration events is less than the calibrated time threshold.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. OTHER RELATED DTCs
1. Turn the ignition on.
2. With the scan tool, read DTCs.

Were there any fuel system or air handling sensor DTCs present?

Yes

- If this DTC is present along with any fuel system or air handling system sensor DTCs, repair those DTCs before proceeding.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 2

2. CHECK THE ENGINE PERFORMANCE
1. Perform the CHECKING ENGINE MISFIRE / RUNS ROUGH / PERFORMANCE TEST diagnostic procedure. Checking Engine Misfire / Runs Rough / Performance Test

Were any problems found?

Yes

- Perform the appropriate repair.
- Perform the DIESEL AFTERTREATMENT VALIDATION - 6.7L procedure. Component Tests and General Diagnostics

No

- Go To 3

3. CHECK FOR THE DIESEL PARTICULATE FILTER DAMAGED
1. Perform the AFTERTREATMENT INSPECTION GUIDELINE - 6.7L procedure. Initial Inspection and Diagnostic Overview

Was any internal damage found in the Diesel Particulate Filter?

Yes

- Replace the Diesel Particulate Filter.
- Perform the DIESEL AFTERTREATMENT VALIDATION - 6.7L procedure. Component Tests and General Diagnostics

No

- Reinstall the exhaust and perform the INTERMITTENT CONDITION - 6.7L. Intermittent Condition Test