P205B

DTC P205B Diesel Exhaust Fluid (DEF) Tank Temperature Sensor Performance

Circuit Description

The DEF level sensor with DEF tank temperature sensor is installed to the DEF tank. The DEF tank temperature sensor measures the temperature of the DEF in the tank.

The intake air temperature (IAT) sensor 1 is fitted between the air cleaner and turbocharger and it measures the temperature of the air entering to the engine. The intake air temperature 1 signal to the DEF control module is sent from the engine control module (ECM) via a controller area network (CAN) communication bus.

The DEF control module monitors temperature difference from both temperature inputs continuously. If the DEF control module detects that both inputs are not within a specified temperature of each other, this DTC will set.

Condition for Running the DTC

- DTCs P205C, P205D and U0100 are not set.
- DTCs P008F, P0097, P0098, P0112, P0113, P0116, P0117, P0118, P0182, P0183, P111D, P111E and P111F are not set in the ECM. (3.0L 4JJ1)
- The battery voltage is between 10 to 16 volts.
- The ignition switch is ON.
- The engine is running.
- The engine coolant temperature is less than 122 °F (50 °C).
- The temperature difference among the intake air temperature 1, the engine coolant temperature and the fuel temperature is less than 9 °F (5 °C) at start up.

Condition for Setting the DTC

Either of following condition is met:
- The DEF control module detects that the DEF temperature in the tank is more than 180 °F (100 °C) over
- The DEF control module detects that the DEF temperature in the tank is more than 35 °F (20 °C) below the intake air temperature 1 for 5 seconds.

Action Taken When the DTC Sets

- The DEF control module requests the ECM to illuminate the MIL on the second consecutive driving cycle. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type B.
- 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

- Use the Temperature vs. Resistance table to test the DEF tank temperature sensor at various temperature levels to evaluate the possibility of a skewed sensor.

The DEF Tank Temperature on the scan tool indicates -40 °F (-40 °C) if this DTC is present.

Circuit / System Testing DTC P205B