AA80E Automatic Transmission

AA80E AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM: P0712,P0713: Transmission Fluid Temperature Sensor "A" Circuit Low Input


DESCRIPTION

The transmission fluid pressure control circuit's fluid temperature is detected using the Automatic Transmission Fluid (ATF) temperature sensor, which is built onto the valve body. Depending on the fluid temperature, a signal is then input into the TCM.





The TCM applies a voltage to the temperature sensor through TCM terminal OIL.

The sensor resistance changes with the ATF temperature. As the temperature becomes higher, the sensor resistance decreases.

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

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





MONITOR DESCRIPTION

The ATF temperature sensor converts ATF temperature to an electrical resistance value. Based on the resistance, the TCM determines the ATF temperature and detects an open or short in the ATF temperature circuit. If the resistance value of the ATF temperature is less than 79 Ohms*1 or more than 156 kOhms*2, the TCM interprets this as a fault in the ATF sensor or wiring. The TCM 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 Techstream display.
MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

P0712: Range check (Low resistance)





P0713: Range check (High resistance)





TYPICAL MALFUNCTION THRESHOLDS

P0712: Range check (Low resistance)





P0713: Range check (High resistance)





COMPONENT OPERATING RANGE





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Perform the universal trip to clear permanent DTCs DTC Check / Clear.

HINT
Using the Techstream 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.

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.

- Warm up the engine.

- Turn the engine switch off.

- Connect the Techstream to the DLC3.

- Turn the engine switch on (IG).

- Turn the Techstream on.

- Enter the following menus: Powertrain / ECT / Data List.

- According to the display on the Techstream, read the Data List.

TCM:





HINT
- When DTC P0712 is output and the Techstream output is 150°C (302°F) or more, there is a short circuit.
- When DTC P0713 is output and the Techstream output is -40°C (-40°F), there is an open circuit. Check the temperature displayed on the Techstream in order to check if a malfunction exists.






HINT
If a circuit related to the ATF temperature sensor becomes open, P0713 is set in approximately 0.5 seconds. It is not necessary to inspect the circuit when P0711 is set.

PROCEDURE

1. CHECK HARNESS AND TRANSMISSION WIRE (TRANSMISSION WIRE - TCM, TRANSMISSION WIRE (ATF TEMPERATURE SENSOR))

(a) Disconnect the TCM connector.





(b) Measure the resistance of the wire harness side connector.

Standard resistance:





HINT
If the resistance is out of the specified range with the ATF temperature shown in the table below, the driveability of the vehicle may decrease.





NG -- CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - TCM)
OK -- Continue to next step.

2. REPLACE TCM

(a) Replace the TCM Service and Repair.

NEXT -- PERFORM A/T CODE REGISTRATION Registration

3. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - TCM)

(a) Disconnect the transmission wire connector.





(b) Disconnect the TCM connector.

(c) Measure the resistance of the wire harness side connectors.

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPAIR OR REPLACE TRANSMISSION WIRE