P040B

DTC PO4OB Exhaust Gas Recirculation (EGR) Temperature Sensor I Circuit Performance

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. If the ECM detects that the actual EGR gas temperature 1 is not within a predetermined range of the calculated value this DTC will set.

Condition for Running the DTC

^ DTCs P0182 P0183 P0237 P0238 P0405 P0406 PO4OC PO4OD P0506 P0507 P0642 P0643 P0652 P0653 P2228 and P2229 are not set.
AND following conditions are met for longer than 10 seconds.
^ The battery voltage is between 10 to 16 volts.
^ The ignition switch is ON.
^ The engine speed is more than 1300 RPM and does not vary more than 50 RPM.
^ The boost pressure does not vary more than 1.5 psi (10 kPa).
^ The fuel temperature is less than 198°F (92°C).
^ The EGR valve position is more than 20% and does not vary more than 5%.
^ The intake airflow valve position is more than 50%.
^ The turbocharger control is under normal operation.
^ The exhaust brake valve is commanded OFF.
^ The DPF regeneration is not running.

Condition for Setting the DTC

^ The ECM detects that the EGR gas temperature 1 (inlet of primary EGR cooler) is not within a predetermined range of the calculated value for 1 second. This indicates an excessively low or high temperature.

Action Taken When the DTC Sets

^ The ECM illuminates the MIL on the second consecutive driving cycle when the diagnostic runs and fails. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type B.
^ The ECM inhibits EGR control.

Condition for Clearing the DTC

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

Diagnostic Aids

^ 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 PO4OB