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Tahoe / Yukon Service Manual

DTC P2459

Engine Controls and Fuel - 3.0L LM2 Diesel | Diagnostic Information and Procedures | Document ID: 5509051 Diagnostic Instructions Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Review Strategy Based Diagnosis for an overview of the diagnostic approach. Diagnostic Procedure Instructions provides an overview of each diagnostic category. DTC Descriptors DTC P2459 Particulate Filter Regeneration Frequency Circuit/System Description The soot particles accumulate in the channels of the DPF and are burned off at regular intervals, through a process called regeneration or cleaning. The diesel particulate filter (DPF) cleaning process prevents the DPF from clogging. Excess soot in filter can cause a drop in engine performance and crack the filter during regeneration. Conditions for Running the DTC Engine = Running Ignition and Start Switch Signal = Greater than 11 V The DTC runs when the above conditions are met. Conditions for Setting the DTC The ECM detects that the actual soot level is greater than an expected soot level when regeneration is triggered. Action Taken When the DTC Sets DTC P2459 is a Type B DTC. Conditions for Clearing the DTC DTC P2459 is a Type B DTC. Reference Information Schematic Reference Engine Controls Schematics Connector End View Reference Master Electrical Component List Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs DTC Type Reference Powertrain Diagnostic Trouble Code (DTC) Type Definitions Scan Tool Reference Control Module References Circuit/System Verification

  1. Ignition ON.
  2. Verify that no other DTCs are set. ⇒ If any other DTCs are set Refer to Diagnostic Trouble Code (DTC) List - Vehicle ⇓ If no other DTCs are set
  3. Verify the conditions listed below do not exist: Any damaged exhaust system components Loose or improperly installed exhaust system components. Leaking exhaust system/turbo charger. Refer to Exhaust Leakage Restrictions in the exhaust differential pressure sensor ports. Damaged, bent, restricted, or kinked exhaust differential pressure lines. Leaking or restricted intake system/charge air hoses. Refer to Component/System Leak Test ⇒ If a condition is found Repair as necessary ⇓ If no condition is found
  4. Ignition ON.
  5. Verify DTC P2459 is not set. ⇒ If the DTC is set 5.1. Perform the Particulate Filter Service Regeneration. Particulate Filter Service Regeneration 5.2. Verify the regeneration completed. ⇒ If the regeneration did not complete, replace the Particulate Filter. ⇓ If no DTC is set
  6. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Nitrogen Oxides Catalytic Converter with Filter Replacement — Particulate Filter Additional Procedures Particulate Filter Reset — Perform only when the following component/system is replaced or serviced: Particulate Filter — Replaced