DTC P042D Exhaust Gas Temperature (EGT) Sensor 2 Circuit High (4JJ3 with DPD)

1. DTC P042D description

Exhaust gas temperature sensor 2 (front of oxidation catalyst) is installed near the inlet of the oxidation catalyst. Exhaust gas temperature sensor 2 (front of oxidation catalyst) is a variable resistor and measures the exhaust gas temperature at the catalytic converter inlet. This sensor has a signal circuit and a low reference circuit. The ECM supplies 5 V to the signal circuit and connects the ground to the low reference circuit. When the exhaust gas temperature is low, the sensor resistance is high, and the higher the exhaust gas temperature becomes, the lower the sensor resistance. The ECM detects a high voltage when the sensor resistance is high, and a low voltage when the sensor resistance is low. If the ECM detects an excessively high signal voltage, the DTC is set.

2. Condition for setting DTC P042D

Condition for running the DTC

  • The battery voltage is 9 to 16 V.
  • The ignition switch is ON.
  • DTCs P0112, P0113, P060B, and P0651 are not set.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC P0112 Intake Air Temperature Sensor Circuit Low".

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC P0113 Intake Air Temperature Sensor Circuit High".

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC P060B Internal Control Module A/D Processing Performance".

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC P0651 Sensor Reference Voltage 2 Circuit".

Also, the following are met for the predetermined time or more:

  • The engine coolant temperature is 75°C {167°F} or more.
  • The engine speed is 1,200 rpm or more.
  • The fuel flow is 10 mm3/st or more.
  • The barometric pressure is 60 kPa {9 psi} or more.
  • Exhaust Gas Temperature 1 is 180°C {356°F} or more.

Condition for setting the DTC

  • The ECM detects that the Exhaust gas temperature sensor 2 (front of oxidation catalyst) signal voltage is 4.9 V or more for 3 seconds.

3. Action taken when DTC P042D sets

  • The ECM illuminates the MIL. Refer to Action taken when DTC sets - Type A.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC type definitions".

  • The ECM assumes a default Exhaust gas temperature sensor 2 (front of oxidation catalyst) value.

4. Condition for clearing DTC P042D

  • Refer to Conditions for clearing the MIL/DTC - Type A or Type B.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC type definitions".

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