AUTOMATIC TRANSMISSION SYSTEM, Diagnostic DTC:P2741

DTC Code DTC Name
P2741 Transmission Fluid Temperature Sensor "B" Performance

DESCRIPTION

The ATF (Automatic Transmission Fluid) temperature sensor converts the ATF temperature into a resistance value which is input into the ECM.

The ECM applies a voltage to the temperature sensor through ECM terminal THO1.

The sensor resistance changes with the ATF temperature.

One terminal of the sensor is grounded so that the sensor resistance and voltage decrease as the temperature becomes higher.

The ECM calculates the ATF temperature based on the voltage signal.

DTC Code DTC Detection Condition Trouble Area
P2741

Either condition is met (2-trip detection logic):

(a) Intake air and engine coolant temperatures are higher than -10°C (14°F) at engine start, and after normal driving for over 19 min. and 8 km (5.0 miles) or more, the ATF temperature is below 20°C (68°F).

(b) Engine coolant temperature is below 35°C (95°F) at engine start, and the ATF temperature is 110°C (230°F) or higher when the engine coolant temperature reaches 60°C (140°F).

 No. 1 ATF temperature sensor (Transmission wire)

MONITOR DESCRIPTION

This DTC indicates that there is a problem with output from the Automatic Transmission Fluid (ATF) temperature sensor and that the sensor itself is defective. The ATF temperature sensor converts the ATF temperature to an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature and detects an open or short in the ATF temperature sensor circuit or a fault in the ATF temperature sensor.

After running the vehicle for a certain period, the ATF temperature should increase. If the ATF temperature is below 20°C (68°F) after running the vehicle for a certain period of time, the ECM interprets this as a fault, turns on the MIL and stores the DTC.

When the ATF temperature is 110°C (230°F) or higher when the engine coolant temperature reaches 60°C (140°F) after a cold start, the ECM also determines this as a fault, turns on the MIL and stores the DTC.

INSPECTION PROCEDURE


  1. DATA LIST

    Tech Tips

    Using the intelligent tester to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

    Note

    In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.


    1. Warm up the engine.

    2. Turn the ignition switch off.

    3. Connect the intelligent tester to the DLC3.

    4. Turn the ignition switch to ON.

    5. Turn the intelligent tester on.

    6. Enter the following menus: Powertrain / Engine and ECT / Data List.

    7. According to the display on the tester, read the Data List.

      Engine and ECT
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      A/T Oil Temperature 1

      No. 1 ATF temperature sensor value/

      Min.: -40°C (-40°F)

      Max.: 215°C (419°F)

      • After stall test: Approximately 80°C (176°F)

      • Equal to ambient temperature when engine cold

      		 If the value is -40°C (-40°F) or 215°C (419°F), the No. 1 ATF temperature sensor circuit is open or shorted.

      Tech Tips

      When DTC P2742 is output and the intelligent tester output is 150°C (302°F) or higher, there is a short circuit.

      When DTC P2743 is output and the intelligent tester output is -40°C (-40°F), there is an open circuit.

      Check the temperature displayed on the tester in order to check if a malfunction exists.

      Temperature Displayed Malfunction
      -40°C (-40°F) Open circuit
      150°C (302°F) or higher Short circuit

      It is not necessary to inspect the circuit when P2741 is stored.

PROCEDURE


  1. CHECK DTC OUTPUT (IN ADDITION TO DTC P2741)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    5. Read the DTCs using the intelligent tester.

      Result
      Result Proceed to
      Only P2741 is output A
      P2741 and other DTCs are output B

      Tech Tips

      If any other codes besides P2741 are output, perform troubleshooting for those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. CHECK TRANSMISSION FLUID LEVEL


    1. Check the transmission fluid level Click here.

      OK
      Automatic transmission fluid level is correct.

    NG

    ADD FLUID Click here

    OK

    REPAIR OR REPLACE NO. 1 ATF TEMPERATURE SENSOR (TRANSMISSION WIRE) Click here