P200C

P200C-DIESEL PARTICULATE FILTER OVER TEMPERATURE - BANK 1





For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams. Electrical Diagrams

Theory of Operation

The Exhaust Temperature Sensors are used by the Electronic Control Module (ECM) to monitor the engine exhaust temperatures in the aftertreatment system. The Exhaust Temperature Sensors are thermistors and change resistance based on the temperature being measured. The ECM provides a 5-volt reference voltage to the sensor. The ECM monitors the voltage on the signal circuit and converts this to a temperature value. When the exhaust gas temperature is cold, the sensor or thermistor resistance is high. The ECM signal voltage only pulls down a small amount through the sensor to ground. Therefore, the ECM senses a high signal voltage or low temperature. When the exhaust gas temperature is hot, the sensor resistance is low. The signal voltage pulls down a large amount. Therefore, the ECM senses a low signal voltage, or a high temperature. The ECM will illuminate the MIL lamp immediately when the diagnostic runs and fails. Active regeneration of the aftertreatment particulate filter will be disabled. This DTC can only be cleared with a scan tool.

- When Monitored:
The diagnostic runs continuously when the engine is running.

- Set Condition:
The Engine Control Module (ECM) detects that the aftertreatment Diesel Particulate Filter outlet temperature is greater than a calibrated temperature for a calibrated period.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. OTHER DTCS
1. Ignition on, engine not running.
2. With the scan tool, read DTCs.

Are any fuel injector DTCs Active?

Yes

- Repair any fuel injector DTCs.

No

- Go To 4

2. INJECTOR RETURN FLOW TEST
1. Perform the INJECTOR RETURN FLOW TEST. Injector Return Flow Test

Did the fuel injectors pass the test?

Yes

- Repair as necessary
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 3

3. CYLINDER MISFIRE
1. Start the engine.
2. Allow the engine to idle.
3. With the scan tool, read the Misfire counter status.

Is an engine misfire detected?

Yes

- Determine the cause of the engine misfire. Use scan tool Cylinder Cutout Test to isolate a failed injector. Replace the failed injector if necessary. Inspect the aftertreatment system for possible damage.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 4

4. CYLINDER MISFIRE
1. Start the engine.
2. Allow the engine to idle.
3. With the scan tool, read the Misfire counter status.

Is an engine misfire detected?

Yes

- Determine the cause of the engine misfire. Use scan tool Cylinder Cutout Test to isolate a failed injector. Replace the failed injector if necessary. Inspect the aftertreatment system for possible damage.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 5

5. EXHAUST TEMPERATURE SENSOR 1/3
1. Turn the ignition off for five minutes.
2. Turn the ignition on.
3. Check the temperature values of the Exhaust Temperature Sensor 1/3 and Exhaust Temperature Sensor 1/1.

Are the aftertreatment diesel particulate filter and diesel oxidation catalyst temperature sensors reading within 25°C (77°F) of each other?

Yes

- Go To 6

No

- Replace the Exhaust Temperature Sensor 1/3. Inspect the aftertreatment system for possible damage.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

6. EXCESSIVE ENGINE OIL BEING INTRODUCED INTO THE AFTERTREATMENT SYSTEM FROM THE ENGINE.
1. Remove the turbocharger outlet and inspect for signs of oil, fuel or moisture being introduced into the aftertreatment system from the engine.

Was engine oil, fuel or moisture found in the turbocharger exhaust outlet?

Yes

- Locate the cause of possible diesel fuel or engine oil being carried from the engine into the aftertreatment system. Inspect the aftertreatment for possible damage.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 7

7. AFTERTREATMENT DIESEL PARTICULATE FILTER
1. Remove and inspect the Aftertreatment Diesel Particulate Filter.

Does aftertreatment Diesel Particulate Filter show evidence of failure?

Yes

- Replace the Aftertreatment Diesel Particulate Filter.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.