P141A

P141A-EXHAUST GAS TEMPERATURE SENSOR 1 AND 2 SIGNALS SWAPPED





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

Theory of Operation

The aftertreatment temperature sensors are used by the Engine Control Module (ECM) to monitor the engine exhaust temperatures in the aftertreatment system. The Exhaust Gas Temperature Sensor 1/1 measures the temperature of the exhaust gas entering the Diesel Oxidation Catalyst. The Exhaust Gas Temperature Sensor 1/2 measures the temperature of the exhaust gas entering the Diesel Particulate Filter. This diagnostic monitor compares the temperatures of the Exhaust Gas Temperature Sensor 1/1 and Exhaust Gas Temperature Sensor 1/2 to ensure that the temperature sensor readings match the anticipated temperature rise as the exhaust gases flow through the Diesel Oxidation Catalyst. This fault code is logged if the ECM detects that the reading from the Exhaust Gas Temperature Sensor 1/1 is higher than the readings from the Exhaust Gas Temperature Sensor 1/2 during an active regeneration event of the Aftertreatment Diesel Particulate Filter. The ECM will illuminate the MIL light immediately when the diagnostic runs and fails. Active regeneration of the Aftertreatment Diesel Particulate Filter will be disabled. The ECM will turn off the MIL light immediately after the diagnostic runs and passes.

- When Monitored:
Engine Running and Performing an Active Regeneration of the Aftertreatment Diesel Particulate Filter.

- Set Condition:
This fault code is logged if the Engine Control Module (ECM) detects that the reading from the Exhaust Gas Temperature Sensor 1/1 is higher than the readings from the Exhaust Gas Temperature Sensor 1/2 during an active regeneration event of the Aftertreatment Diesel Particulate Filter.





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

1. P141A ACTIVE
1. The diagnostic procedure is different depending on body style.
2. On DH/D1 vehicles the connectors can not be physically reversed.
3. On Cab Chassis vehicles the connectors can be physically reversed.

Is this a DH/D1 or a Chassis Cab vehicle?

DH/D1

- Go To 4

Chassis Cab

- Go To 2

2. EXHAUST TEMPERATURE SENSOR
1. The Exhaust Gas Temperature Sensor 1/1 and the Exhaust Gas Temperature Sensor 1/2 readings are reversed.
2. Swap the wiring harness connectors of the Exhaust Gas Temperature Sensor 1/1 and the Exhaust Gas Temperature Sensor 1/2.
3. Erase the DTC with the scan tool.
4. Perform a Mobile Desoot.
5. With the scan tool, read DTCs.

Did the DTC reset?

Yes

- Replace both Exhaust Gas Temperature Sensors and put the wiring harness connectors back to their original positions.
- Go To 3

No

- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST (6.7L). Powertrain Verification Test.

3. DAMAGED/NONFUNCTIONAL AFTERTREATMENT DIESEL OXIDATION CATALYST
1. Erase the DTC with the scan tool.
2. Perform a Mobile Desoot.
3. With the scan tool, read DTCs.

Did the DTC reset?

Yes

- Replace the Aftertreatment Diesel Oxidation Catalyst.
- Perform the POWERTRAIN VERIFICATION TEST (6.7L). Powertrain Verification Test.

No

- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST (6.7L). Powertrain Verification Test.

4. EXHAUST TEMPERATURE SENSORS
1. Replace the Exhaust Gas Temperature Sensor 1/1 and the Exhaust Gas Temperature Sensor 1/2.
2. Erase the DTC with the scan tool.
3. Perform a Mobile Desoot.
4. With the scan tool, read DTCs.

Did the DTC reset?

Yes

- Replace the Aftertreatment Diesel Oxidation Catalyst.
- Perform the POWERTRAIN VERIFICATION TEST (6.7L). Powertrain Verification Test.

No

- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST (6.7L). Powertrain Verification Test.