P2463

DTC P2463

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 P2463
- Diesel Particulate Filter Soot Level Accumulation

Circuit/System Description

The particulates in the exhaust gases are collected by the diesel particulate filter (DPF). When the filter becomes saturated with particulates, they are incinerated by a regeneration process. The regeneration process increases the exhaust gas temperature, warming the diesel oxidation catalyst (DOC) first, then warming the DPF. The engine control module (ECM) monitors the system with inputs from two exhaust gas temperature (EGT) sensors 1 and 2 and an exhaust differential pressure sensor.

The ECM will command an active regeneration base on a calculated soot model. The soot model calculations are based on the following information:

* Distance since last DPF regeneration
* Fuel used since last DPF regeneration
* Engine run time since last DPF regeneration
* Exhaust differential pressure sensor values

If soot loading continues to increase it will eventually exceed a calibrated threshold and cause this diagnostic to run and fail.

Conditions for Running the DTC

* The ignition is ON.
* DTC P2463 runs continuously when the above condition is met.

Conditions for Setting the DTC

* The ECM has determined that the soot level within the DPF has exceeded a calibrated threshold.
* The condition exists for greater than 5 minutes.

Action Taken When the DTC Sets

* DTC P2463 is a Type A DTC.
* The control module commands the engine control system to operate in Reduced Engine Power mode.
* A message center or an indicator may display Reduced Engine Power.
* The DPF regeneration is inhibited.

Conditions for Clearing the MIL/DTC

DTC P2463 is a Type A DTC.

Diagnostic Aids

* A skewed or shifted exhaust differential pressure sensor will cause inaccuracies in the soot model and may cause this DTC to set.
* Exhaust leaks in the exhaust system may cause inaccurate gas temperature sensor or exhaust differential pressure values causing this DTC to set.
* Improperly installed or loose exhaust gas temperature (EGT) sensors 1 and 2 will cause inaccuracies in the soot model and cause this DTC to set.
* Low engine compression may cause this DTC to set.
* Not operating the vehicle under the proper conditions to perform a full and effective regeneration OR ignoring the Clean Exhaust Filter message may cause this DTC to set.

Circuit/System Verification

1. Verify that DTCs P003A, P0047, P0048, P0101, P0201-P0208, P02A1, P02A5, P02A9, P02AD, P02B1, P02B5, P02B9, P02E0, P02E7-P02E9, P029D, P0234, P0299, P0300-P0308, P0401, P0402, P046C, P0545, P0546, P0698, P0699, P2032, P2033, P2453, or P2563 are not set.

• If any of the DTCs are set, Refer to Diagnostic Trouble Code (DTC) List - Vehicle. Diagnostic Trouble Code Descriptions

2. Verify the following scan tool parameters:

* Engine Run Time Since Last DPF Regeneration parameter-The value should be less than 22 hours.
* Fuel Used Since Last DPF Regeneration parameter-The value should be less than 272 liters (71 gallons).
* Distance Since Last DPF Regeneration parameter-The value should be less than 1,030 kilometers (640 miles) at sea level, or less than 643 kilometers (400 miles) when equal to or above 10,000 feet altitude.

• If any of the parameters are greater than the specified range, perform a DPF Service Regeneration. Refer to Exhaust Particulate Filter Cleaning (DPF Service Regeneration) Exhaust Particulate Filter Cleaning (DPF Regeneration Enable).

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame Records data.

Circuit/System Testing

1. Visually inspect the exhaust differential pressure system for any of the following conditions:

* Modifications
* Damaged components
* Bends or kinks
* Loose or improperly installed components
* Improperly routed differential pressure lines
The exhaust differential pressure line should have a continuous downward gradient from the sensor.

2. Verify that restrictions do not exist in the exhaust particulate filter. Refer to Restricted Exhaust. Restricted Exhaust

• If a condition is found, replace the particulate filter.

3. Remove and visually inspect the flexible part of the exhaust differential pressure lines for internal restrictions.

• If a condition is found, replace the exhaust differential pressure lines.

4. Ignition ON, observe the scan tool EGR Position Variance parameter while commanding the EGR solenoid to 20 percent and 0 percent. The values should remain equal to or less than 3 percent.

• If greater than the specified range, replace the EGR valve.

5. Test the EGR valve gaskets and cooler gaskets for leaks. Apply a soap solution to the gaskets while commanding the TC Vane Pos. Ctrl. Solenoid ON, and inspect for excessive air bubbles at the EGR valve gaskets and cooler gaskets.

• If an air leak is found, replace the EGR valve gaskets or EGR cooler gasket.

6. Test the fuel system for leaking fuel injectors, high fuel pressures, or high fuel injector flow rates.
7. Test the charge air cooler (CAC) for leaks.
8. Ignition OFF, disconnect the harness connector at the exhaust differential pressure sensor.
9. Ignition OFF for 90 seconds, test for less than 5 ohms of resistance between the low reference circuit terminal 1 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.

10. Disconnect the harness connector X1 at the ECM.
11. Test for less than 5 ohms of resistance on the differential pressure sensor circuits between the following terminals:

* ECM X1 5 volt reference circuit terminal 14 to exhaust differential pressure sensor terminal 3.
* ECM X1 signal circuit terminal 43 to exhaust differential pressure sensor terminal 2.

• If greater than the specified range, repair the affected circuit for an open/high resistance.

12. If all circuits and engine control components test normal, test or replace the exhaust differential pressure sensor.

Component Testing

Important: You must perform the Circuit/System Testing in order to verify the integrity of the exhaust differential pressure sensor circuits before proceeding with Component Testing.

1. Ignition OFF, remove the exhaust pressure differential pressure sensor.
2. Install a 3A fused jumper wire between the 5-volt reference circuit terminal C and the corresponding terminal of the differential sensor. Install a jumper wire between the low reference terminal A of the sensor and ground.
3. Install a jumper wire between the low reference circuit terminal A of the differential sensor and ground.
4. Install a jumper wire at terminal B of the differential sensor.
5. Connect a DMM between the jumper wire from terminal B of the differential sensor and ground.
6. Ignition ON, with the J 23738-A or J 35555 connected to the pressure sensor rear pressure port, slowly apply vacuum to the sensor while monitoring the voltage between the signal terminal B and the low reference terminal A. The voltage should vary between 4.8-0.4 volts without any spikes or dropouts.

• If the voltage is erratic, replace the differential sensor.

Repair Instructions

Notice: After performing the system repair, perform the following:

* A code clear with a scan tool, regardless of whether or not a DTC is set

* A Diesel Particulate Filter (DPF) Service Regeneration with a scan tool

Perform the above in order to remove soot from the DPF and avoid possible DPF failure.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

* Exhaust Particulate Filter Cleaning (DPF Service Regeneration) Exhaust Particulate Filter Cleaning (DPF Regeneration Enable) for Service Regeneration.
* Exhaust Pressure Differential Sensor Replacement
* Exhaust Particulate Filter Replacement (6.6L (LMM)) Verification Tests