For 1990-2009 cars

### 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 Descriptor

DTC P2458 51: Diesel Particulate Filter (DPF) Regeneration Time
DTC P2458 56: Diesel Particulate Filter (DPF) Regeneration Time
DTC P2458 57: Diesel Particulate Filter (DPF) Regeneration Time

### 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 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

• | The engine is running.

• | The engine coolant temp (ECT) is between 73-96°C (163-205°F).

### Conditions for Setting the DTC

• | The ECM detect to long regeneration times

• | The above condition is met.

### Action Taken When the DTC Sets

DTC P2458 is a Type C DTC.

### Conditions for Clearing the DTC

DTC P2458 is a Type C DTC.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### 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 for scan tool information

### Circuit/System Verification

1. The following conditions must be met for the ECM to perform the turbocharger learn procedure:

• | The A/C is OFF.

• | The vehicle is in Park or Neutral.

• | Start and idle the engine.

• | The engine coolant temperature (ECT) is greater than 40°C (104°F).

2. Perform the DPF Service Regeneration.
3. Verify the DTC does not reset.

⇒ | If the DTC resets, replace the DPF filter.