P0712

U760E AUTOMATIC TRANSMISSION / TRANSAXLE: AUTOMATIC TRANSAXLE SYSTEM: P0712, P0713: Transmission Fluid Temperature Sensor "A" Circuit Low Input


DESCRIPTION

The Automatic Transmission Fluid (ATF) temperature sensor converts the fluid temperature into a resistance value for use by the ECM.





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

The sensor resistance changes with the transmission fluid 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 goes down as the temperature becomes higher.

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





MONITOR DESCRIPTION

These DTCs indicate an open or short in the automatic transmission fluid (ATF) temperature sensor circuit. The automatic transmission fluid (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 79 Ohms*1 or more than 156 kOhms*2, the ECM interprets this as a fault in the ATF sensor or wiring. The ECM will turn on the MIL and store the DTC.

*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.

HINT
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)

- One of the following conditions is met: Condition (A) or (B)

Condition (A)





Condition (B)





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 Reading and Clearing Diagnostic Trouble Codes.

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.

1. Warm up the engine.

2. Turn the ignition switch off.

3. Connect the Techstream to the DLC3.

4. Turn the ignition switch to ON.

5. Turn the Techstream on.

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

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

ECM





HINT
When DTC P0712 is output and the Techstream indicates 150°C (302°F) or more, there is a short circuit.

When DTC P0713 is output and the Techstream indicates -40°C (-40°F), there is an open circuit.

Measure the resistance between terminal THO1 (OT) and body ground.





HINT
If the circuit related to the ATF temperature sensor becomes open, P0713 is immediately set (in 0.5 seconds). When P0713 is set, P0711 cannot be detected.

It is not necessary to inspect the circuit when P0711 is set.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (ATF TEMPERATURE SENSOR CIRCUIT)

(a) Disconnect the ECM connector.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- CHECK HARNESS AND CONNECTOR (ECM - WIRING HARNESS CONNECTOR)

OK -- REPLACE ECM Components

2. CHECK HARNESS AND CONNECTOR (ECM - WIRING HARNESS CONNECTOR)

(a) Disconnect the harness connector from the wiring harness connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. INSPECT TRANSMISSION WIRE (ATF TEMPERATURE SENSOR)

(a) Remove the wiring harness connector from the transaxle.





(b) Measure the resistance according to the value(s) in the table below.

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.





Text in Illustration





NG -- REPLACE TRANSMISSION WIRE (ATF TEMPERATURE SENSOR) Components

OK -- REPLACE WIRING HARNESS CONNECTOR Components