P244C

DTC P244C

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 provide an overview of each diagnostic category.

DTC Descriptor

DTC P244C
- Catalyst Temperature Too Low During Regeneration

Circuit/System Description

The diesel oxidation catalyst (DOC) converter controls emissions of non methane hydro carbons (NMHC), carbon monoxide (CO), and oxides of nitrogen (NOx). The DOC is also utilized to regenerate the exhaust particulate filter. The engine control module (ECM) monitors the exhaust gas temperature (EGT) sensor 1 during regeneration to determine if regeneration temperatures are maintained.

If the ECM detects that the DOC cannot maintain a pre-determined temperature during a regeneration event this DTC may run and fail, and the regeneration event aborts.

Conditions for Running the DTC

* The engine control system is in an active regeneration.
* DTC P244C runs continuously when the above condition is met.

Conditions for Setting the DTC

* The ECM determines that the EGT sensor 1 is less than 75°C (167°F) of a calibrated threshold, during an active regeneration event.
* The condition exists for greater than 5 minutes.

Action Taken When the DTC Sets

* DTC P244C is a type A DTC.
* Regeneration will be inhibited.

Conditions for Clearing the DTC

DTC P244C is a type A DTC.

Diagnostic Aids

The use of 500 ppm sulfur non-road diesel fuel containing red dye or the use of non ultra low sulfur fuel in the vehicle may be a possible contributor to the degradation of metals in the DOC. A degraded DOC will not light off, and properly maintain the necessary heat required to completely regenerate the particulate filter.
* Scan Tool Data Definitions

Circuit/System Verification

1. If any other DTCs are set, diagnose those codes first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle. Diagnostic Trouble Code Descriptions
2. Inspect the DOC for any of the following abnormal conditions:

* Physical damage or alterations
* Severe discoloration caused by excessive temperatures
* Internal rattles caused by a damaged catalyst substrate
* Internal restrictions-Refer to Restricted Exhaust. Restricted Exhaust

• If a condition is found, replace the DOC.

3. Inspect the exhaust system for the following conditions:

* Restrictions-Refer to Restricted Exhaust. Restricted Exhaust
* Exhaust leaks
* Physical damage or alterations

• If a condition is found, repair the exhaust system as necessary.

4. Inspect for the following conditions, which may cause a DOC to degrade:

* An engine misfire
* Engine oil or coolant consumption
* Leaking fuel injectors
* A fuel that does not meet the ultra low sulfur requirements, red dye fuel, or off road diesel fuel
* Contaminated fuel-Refer to Contaminants-in-Fuel Diagnosis. Contaminants-in-Fuel Diagnosis

• If a condition is found, repair as necessary, then replace the DOC.

5. If all inspections and tests are normal, replace the DOC.

Repair Instructions

* Perform a scan tool DPF service regeneration.
* Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Catalytic Converter Replacement (Dual Exhaust - Left) Catalytic Converter Replacement (Dual Exhaust - Right) Catalytic Converter Replacement (Single Exhaust - 4.3L, 4.8L and 5.3L) Catalytic Converter Replacement (6.6L (LBZ/LLY)) Catalytic Converter Replacement (6.6L (LMM))