P040D

DTC P040D Exhaust Gas Recirculation (EGR) Temperature Sensor 1 Circuit High Voltage

Circuit Description

The exhaust gas recirculation (EGR) gas temperature sensor 1 is installed to the EGR cooler adapter. The EGR gas temperature sensor 1 is a variable resistor and it measures the temperature of the exhaust gas inlet of primary EGR cooler. The sensor has a signal circuit and a low reference circuit. The ECM supplies 5 volts to the signal circuit and a ground for the low reference circuit. When the EGR gas temperature sensor 1 is cold the sensor resistance is high. When the exhaust temperature increases the sensor resistance decreases. With higher sensor resistance the ECM detects a high voltage on the signal circuit. With lower sensor resistance the ECM detects a lower voltage on the signal circuit. If the ECM detects an excessively high signal voltage this DTC will set.

Condition for Running the DTC

^ DTCs P0112 P0113 and PO4OC are not set.
^ The battery voltage is between 10 to 16 volts.
^ The ignition switch is ON.
^ The engine runtime is longer than 7 minutes.
^ The engine speed is more than 1600 RPM.
^ The fuel injection quantity is more than 40 mm3.

Condition for Setting the DTC

^ The ECM detects that the EGR gas temperature sensor 1 (inlet of primary EGR cooler) signal voltage is more than 4.9 volts for 1 second.

Action Taken When the DTC Sets

^ The ECM illuminates the MIL when the diagnostic runs and fails. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type A.
^ The ECM inhibits EGR control.

Condition for Clearing the DTC

^ Refer to DTC Type Definitions for Condition for Clearing the MIL/DTC - Type A.

Diagnostic Aids

^ If an intermittent condition is suspected refer to Intermittent Conditions in this section.
^ Use the Temperature vs. Resistance table to test the EGR gas temperature sensor 1 at various temperature levels to evaluate the possibility of a skewed sensor.

Circuit/System Testing DTC P040D