P242B

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





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

Theory of Operation

The Exhaust Temperature Sensors are used by the Powertrain Control Module (PCM) to monitor the engine exhaust temperatures in the after treatment 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 PCM and share a sensor ground. The PCM monitors the change in signal voltage and converts this to a temperature value. The PCM illuminates the MIL lamp when the monitor runs and fails in two consecutive trips. 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 PCM will turn off the MIL lamp immediately after the diagnostic runs and passes. The PCM will turn off the MIL light immediately after the diagnostic runs and passes in four consecutive drive cycles.

- When Monitored:
Engine Running.

- Set Condition:
The Powertrain Control Module (PCM) 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. OTHER DTCs PRESENT
1. Turn the ignition on.
2. With the scan tool, read DTCs.

Are either of the Exhaust Temperature Sensor 1/3 Low or High DTCs present?

Yes

- Repair the other DTCs before proceeding.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 2

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 5°F on the scan tool?

Yes

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test

No

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