P242B

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





For a complete wiring diagram Refer to Diagrams/Electrical.

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 pin and converts this to a temperature value. This fault is set by the ECM if it detects that the aftertreatment diesel particulate filter outlet temperature sensor reading is not increasing with engine operating temperature after engine startup. The ECM illuminates the MIL lamp immediately when the diagnostic runs and fails. Regeneration of the aftertreatment 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 reading is not increasing with engine operating temperature after engine startup.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview


Diagnostic Test


1. OTHER DTCS
With a scan tool read DTCs.
Do you have any other DTC for the Exhaust Gas Temperature sensors?

Yes


- Repair all other DTCs first.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Go To 2
-



2. EXHAUST TEMPERATURE SENSOR 1/3
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 - DIESEL Diagnostic Procedure. Intermittent Condition


No


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