P0712
U341E AUTOMATIC TRANSAXLE: AUTOMATIC TRANSAXLE SYSTEM: P0712, P0713: Transmission Fluid Temperature Sensor "A" Circuit Low Input
DESCRIPTION
The ATF (Automatic Transmission Fluid) temperature sensor converts the fluid temperature into a resistance value which is input into the ECM.
The ECM applies a voltage to the temperature sensor through ECM terminal THO1 (THO).
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 (TFT sensor) circuit. The automatic transmission fluid (ATF) temperature sensor converts ATF temperature to an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature, and the ECM detects opens or shorts 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 a Techstream display.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
P0712: Range check (Low resistance)
P0713: Range check (High resistance)
Condition (A)
Condition (B)
Condition (C)
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 a 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. READ DATA LIST
(a) Warm up the engine.
(b) Turn the ignition switch off.
(c) Connect the Techstream to the DLC3.
(d) Turn the ignition switch to ON.
(e) Turn the Techstream on.
(f) Enter the following menus: Powertrain / Engine and ECT / Data List.
(g) According to the display on the Techstream, read the Data List.
HINT
When DTC P0712 is output and Techstream output is 150°C (302°F), there is a short circuit.
When DTC P0713 is output and Techstream output is -40°C (-40°F), there is an open circuit.
Measure the resistance between terminal THO1 (THO) and body ground.
HINT
If a 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. INSPECT TRANSMISSION WIRE (ATF TEMPERATURE SENSOR)
(a) Disconnect the transmission wire connector from the transaxle.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for open):
Standard Resistance (Check for short):
HINT
If the resistance is out of the specified range for any of the ATF temperatures shown in the table below, the driveability of the vehicle may decrease.
NG -- REPAIR OR REPLACE TRANSMISSION WIRE Removal
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM)
(a) Connect the transmission wire connector to the transaxle.
(b) Disconnect the ECM connectors.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for open):
Standard Resistance (Check for short):
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM Removal