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 Descriptors

DTC P2463: Diesel Particulate Filter Soot Accumulation
DTC P2463 11: Diesel Particulate Filter Soot Accumulation Above Maximum Threshold

### Circuit/System Description

The diesel exhaust after-treatment system consists of an under hood pre-catalytic converter and an underbody catalytic converter. The underbody catalytic converter also consists of the main Diesel Oxidation Catalyst (DOC) and the coated Diesel Particulate Filter (DPF). One of the main purposes of the DPF is to collect particulates from the engine exhaust in order to minimize discharge of soot to the atmosphere. The soot particles accumulate in the channels of the DPF and are burned off at regular intervals through a process called regeneration. This prevents the DPF from clogging. The ECM commands the DPF regeneration after calculating various vehicle conditions such as DPF pressure difference, exhaust gas temperature, engine oil quality, engine speed, etc. Excessive accumulation of the soot in the DPF can cause a drop in the engine performance. During regeneration, additional fuel is injected via multiple post injections in order to increase the exhaust gas temperature. During this period, the DPF temperature is raised to approximately 600°C and the accumulated soot is oxidized or burned off into carbon dioxide (CO2).

The DPF pressure sensor measures the level of soot deposit in the DPF. The DPF pressure sensor is connected to the DPF with pressure pipes/hoses. The ECM performs a regeneration when excessive soot level is detected in the filter.

### Conditions for Running the DTC

• | The engine is running.

• | The DTC runs continuously when the above condition is met.

### Conditions for Setting the DTC

The ECM detects that the particulate mass in the DPF is greater than 50 grams.

### Action Taken When the DTC Sets

DTC P2463 is a type A DTC.

### Conditions for Clearing the DTC

DTC P2463 is a type A 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. Ignition ON, observe the DTC information with a scan tool. Verify that no other DTCs are set.

⇒ | If any other DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

2. Verify the correct fuel type is used. Refer to Fuel System Specifications.

⇒ | If the incorrect fuel type is used, refer to Fuel System Cleaning.

3. Engine running, observe the scan tool diesel particulate filter data parameter. The reading should be within 0-10 kPa (0-1.5 psi).

Important: Observe the scan tool distance since last DPF regeneration data parameter. Do Not perform a DPF regeneration if it has been performed recently.

⇒ | If not within the specified range, perform a DPF regeneration.

4. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

### Circuit/System Testing

1. Ignition OFF, inspect the hose/pipes to the DPF pressure sensor for leaks, or restrictions.

⇒ | If a condition is found, repair as necessary.

2. Ignition OFF, and the MAIN fuse removed, disconnect the harness connector at the DPF sensor.
3. Test for less than 5 ohms between the low reference circuit terminal 2 and ground.

⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

4. Install the MAIN fuse. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 1 and ground.

⇒ | If less than the specified range, test the 5-volt reference circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the ECM.

⇒ | If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

5. Verify the scan tool DPF sensor parameter is greater than 4.8 volts.

⇒ | If less than the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM.

6. Install a 1A fused jumper wire between the signal circuit terminal 3 and ground. Verify the DPF sensor parameter is less than 0.5 volts.

⇒ | If greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.

7. Ignition OFF, connect the harness connector at the DPF pressure sensor.
8. Ignition ON, verify the scan tool DPF pressure sensor parameter is between 0.45-0.55 volts.

⇒ | If not within the specified range, replace the DPF sensor.

9. If all circuits test normal, test or replace the DPF.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Exhaust Pressure Sensor Replacement

• | Exhaust Particulate Filter Replacement

• | Control Module References for ECM replacement, programming and setup.

### Repair Verification

Ignition ON, observe the scan tool DPF soot mass parameter. The parameter should be less than 5 grams.

⇒ | If greater than the specified range, perform a DPF service regeneration. Refer to Exhaust Particulate Filter Cleaning.