P242B

P242B-EXHAUST GAS TEMP SENSOR CIRCUIT PERFORMANCE - BANK 1 SENSOR 3 - DIESEL





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

Theory of Operation

The Exhaust Temperature Sensors are used by the Engine 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 Exhaust Temperature Sensors receive a 5-volt signal from the ECM and share a sensor ground. The ECM monitors the change in signal voltage and converts this to a temperature value. The ECM illuminates the MIL lamp immediately when the diagnostic runs and fails. A default value will be used for the Exhaust Temperature Sensor 1/3 and active regeneration of the diesel particulate filter will be disabled. The ECM will turn off the MIL lamp immediately after the diagnostic runs and passes.

- When Monitored:
Engine Running.

- Set Condition:
The ECM detects that the Exhaust Temperature Sensor 1/3 reading is not increasing with engine operating temperature after engine startup.





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

1. ACTIVE DTC

NOTE: If Exhaust Temperature Sensor 1/3 Low or High DTCs are present repair those DTCs before proceeding.

1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 30 seconds.
5. Start the engine. It may be necessary to drive the vehicle in order to reset the DTC.
6. With the scan tool, read DTCs.

Did the DTC reset?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION - DIESEL (Diagnostic Procedure). Intermittent Condition Test

2. EXHAUST TEMPERATURE SENSOR 1/3
1. Remove the Exhaust Temperature Sensor 1/3 and reconnect the harness connector to the sensor. Monitor the scan tool, while heating the sensor with an external heat source (DO NOT USE OPEN FLAME).

Does the reading from the sensor increase at least -15°C (5°F) on the scan tool?

Yes

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition Test

No

- Replace the Exhaust Temperature Sensor 1/3.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test