P2743

DTC P2740 Transmission Fluid Temperature Sensor "B" Circuit

DTC P2742 Transmission Fluid Temperature Sensor "B" Circuit Low Input

DTC P2743 Transmission Fluid Temperature Sensor "B" Circuit High Input

DESCRIPTION
The Automatic Transmission Fluid (ATF) temperature sensor is on the transmission, just in front of the oil cooler inlet pipeline.
If the ECM detects an abnormally high ATF temperature near this sensor, it illuminates the warning light.

HINT:
- The temperature of ATF easily rises when towing, climbing hills, in traffic, etc.
- If the ATF temperature sensor becomes short-circuited, the signal that indicates that the ATF temperature is 150°C (302°F) or higher is input into the ECM. Vehicle conditions when the sensor is normal and when the sensor is short-circuited are indicated in the table below.





HINT:
*1: When ATF temperature is in the normal range, it decreases to less than 135°C (275°F) within 5 minutes with the shift lever in the P or N position in an idling state.
*2: When ATF temperature is normal, transmission lock-up occurs in 5th gear with the shift lever in the D position, and 4th gear with the shift lever in the 4 position.








MONITOR DESCRIPTION
The ATF temperature sensor converts ATF temperature into an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature, and the ECM detects an open or short in the ATF temperature circuit. If the resistance value of the ATF temperature is less than 25 Ohms*1 or more than 156 kOhms*2, the ECM interprets this as a fault in the ATF sensor or wiring. The ECM will illuminate the MIL and store the DTC.

HINT:
- *1: 150°C (302°F) or more is indicated regardless of the actual ATF temperature.
- *2: -40°C (-40°F) is indicated regardless of the actual ATF temperature.
- The ATF temperature can be checked on the intelligent tester or Techstream display.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS

Part 1:

Part 2:

COMPONENT OPERATING RANGE

Wiring Diagram:

INSPECTION PROCEDURE
1. DATA LIST

HINT: Using the intelligent tester or Techstream Data List allows switch, sensor, actuator and other item values to be read without removing any parts. Reading the Data List early in troubleshooting is one way to save time.

NOTICE: 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.

(a) Warm up the engine.
(b) Turn the ignition switch OFF.
(c) Connect the intelligent tester or Techstream to the DLC3.
(d) Turn the ignition switch ON and push the tester switch ON.
(e) Enter the following menus:
(1) Intelligent tester - Select: DIAGNOSIS / OBD/MOBD / ECT / DATA LIST /
(2) Techstream - Select: Powertrain / Engine and ECT / Data List /
(f) Follow the instructions on the tester and read the Data List.
(1) Intelligent tester

ECT:

(2) Techstream

ECT:

HINT:
^ When DTC P2742 is output and the intelligent tester or Techstream output is 150°C (302°F) or more, there is a short circuit.
^ When DTC P2743 is output and the intelligent tester or Techstream output is -40°C (- 40°F), there is an open circuit. Measure the resistance between terminal THO2 and the body ground.

Step 1-2: