DTC P2742: Transmission Fluid Temperature Sensor "B" Circuit Low Input; DTC P2743: Transmission Fluid Temperature Sensor "B" Circuit High Input: Description

The No. 2 Automatic Transmission Fluid (ATF) temperature sensor is on the transmission, just before the oil cooler inlet pipeline.

If the ECM detects an abnormally high ATF temperature through this sensor, it illuminates the warning light to indicate the problem to the driver.

HINT:

The ATF temperature is liable to increase under vehicle conditions such as towing, climbing hills and in traffic.

If there is a short malfunction in the No. 2 ATF temperature sensor, the ECM receives signals from the sensor, which indicate that the ATF temperature is 150°C (302°F) or more.

THE SYMPTOMS AND RECOVERY CONDITIONS, WHEN THE SENSOR IS NORMAL OR THERE IS A SHORT MALFUNCTION IN THE SENSOR, ARE AS SHOWN IN THE TABLE BELOW.

No. 2 ATF Temperature Sensor Status	Detection Condition	Symptom	Recovery Condition
Sensor is normal	ATF temperature more than 150°C (302°F)	ATF temperature warning light remains on	ATF temperature less than 135°C (275°F) *2
	ATF temperature more than 130°C (266°F)	Shift point too high	ATF temperature less than 110°C (230°F)
	When the conditions (a) and (b) are satisfied continually (a) ATF temperature more than 130°C (266°F) (b) Engine coolant temperature more than 95°C (203°F)	Lock-up in 3rd gear *1	ATF temperature less than 110°C (230°F) *2 and engine coolant temperature less than 95°C (203°F)
Sensor is short	Any conditions	ATF temperature warning light remains on Shift point too high	Symptoms still occur
Sensor is short	Engine coolant temperature more than 95°C (203°F)	Lock-up in 3rd gear *1	Symptom still occurs

HINT:

*1: When the ATF temperature is normal, the transmission locks up in 5th gear with the shift lever in the D position and in 4th gear with the shift lever in the 4th position.

*2: When the ATF temperature is in the normal range, it decreases to less than 135°C (275°F) within 5 minutes of the shift lever being moved to the P or N position, while idling.

DTC No.	DTC Detection Conditions	Trouble Areas
P2742	No. 2 ATF temperature sensor resistance (voltage) is less than 25 Ω (0.046 V) for 0.5 seconds or more (1-trip detection logic).	Short in No. 2 ATF temperature sensor circuit No. 2 ATF temperature sensor ECM
P2743	No. 2 ATF temperature sensor resistance is more than 156 kΩ (4.915 V) for 0.5 seconds or more, and either of the following conditions is met (1-trip detection logic):	Open in No. 2 ATF temperature sensor circuit No. 2 ATF temperature sensor ECM
	(A) 15 minutes or more have elapsed after the engine start when engine coolant temperature or intake air temperature is -29.375°C (-20.875°F) or less.
	(B) 10 seconds or more have elapsed after the engine start when engine coolant temperature and intake air temperature are more than -29.375°C (-20.875°F).