P242D

DTC P242D Exhaust Gas Temperature (EGT) Sensor 3 Circuit High Voltage

Circuit Description

The exhaust gas temperature (EGT) sensor 3 is installed to the front chamber of SCR catalyst housing. The EGT sensor 3 is a resistance temperature detector type sensor and it measures the temperature of the exhaust gas in the front of SCR catalyst. The sensor has a signal circuit and a low reference circuit. When the exhaust gas temperature is low, the sensor resistance is low and the DEF control module detects a low voltage on the signal circuit. When the exhaust gas temperature increases, the sensor resistance increases and the DEF control module detects a higher voltage on the signal circuit. If the DEF control module detects an excessively high signal voltage, this DTC will set.

Condition for Running the DTC
- DTC P060B is not set.
- The battery voltage is between 10 to 16 volts.
- The ignition switch is ON.

Condition for Setting the DTC

- The DEF control module detects that the EGT sensor 3 signal voltage is greater than 2.04 volts (1382 °F [750 °C]) for 2 seconds. (3.0L 4JJ1)

Action Taken When the DTC Sets

- The DEF control module requests the ECM to illuminate the MIL. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type A.
- The DEF control module and the ECM apply defaulted warning actions. Refer to Default Action and Fail- Safe List.

Conditions for Clearing the DTC

- Refer to DTC Type Definitions for Conditions for Clearing the DTC - Type A or Type B.

Diagnostic Aids

- If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
- Use the Temperature vs. Resistance table to test the EGT sensor 3 at various temperature levels to evaluate the possibility of a skewed sensor.

The EGT 3 parameter on the scan tool indicates 122 °F (50 °C) if this DTC is active.

Circuit / System Testing DTC P242D