DTC P0712 Transmission Fluid Temperature Sensor Circuit Low Input: Wiring Diagram

WARNING: This page is about a different variant/trim than selected.

Fig 1: Transmission Fluid Temperature Sensor Circuit Diagram (Low Input)

Courtesy of SUBARU OF AMERICA, INC.

Step	Check	Yes	No
1 CHECK HARNESS CONNECTOR BETWEEN TCM AND TRANSMISSION. Turn the ignition switch to OFF. Disconnect the connectors from TCM and transmission. Measure the resistance of harness between TCM connector and transmission connector. Connector & terminal (B55) No. 17 - (B11) No. 5: (B55) No. 18 - (B11) No. 12:	Is the resistance less than 1 Ω?	Go to step 2.	Repair the open circuit of harness between TCM and transmission connector.
2 CHECK ATF TEMPERATURE SENSOR. Turn the ignition switch to OFF. Connect the connectors to transmission and TCM. Start the engine. Warm up the transmission until the ATF temperature exceeds 80°C (176°F). Disconnect the connector from transmission. Measure the resistance between transmission connector terminals. Connector & terminal (T4) No. 5 - (T4) No. 12:	Is the resistance 300 - 800 Ω?	Go to step 3.	Go to step 5 .
3 CHECK ATF TEMPERATURE SENSOR. Measure the resistance between transmission connector terminals. Connector & terminal (T4) No. 5 - (T4) No. 12:	Does the resistance value increase while the ATF temperature decreases?	Go to step 4.	Go to step 5 .
4 CHECK INPUT SIGNAL FOR TCM. Connect the connector. Turn the ignition switch to ON. Read the data of "ATF Temp." using Subaru Select Monitor.	Does the ATF temperature gradually decrease?	Check for poor contact of the harness between the ATF temperature sensor and transmission connector, and repair the fault location.	Go to step 6 .
5 CHECK HARNESS CONNECTOR BETWEEN TRANSMISSION AND CONTROL VALVE BODY. Turn the ignition switch to OFF. Disconnect the connector from transmission. Remove the transmission connector from bracket. Lift up the vehicle. Drain the ATF. CAUTION: Do not drain ATF until it cools down. Remove the oil pan. Disconnect the control valve body connector. Measure the resistance between transmission connector and control valve body connector. Connector & terminal (T4) No. 5 - (T10) No. 3: (T4) No. 12 - (T10) No. 4:	Is the resistance less than 1 Ω?	Replace the control valve body. Refer to CONTROL VALVE BODY 5AT-55, Control Valve Body.	Repair the open circuit of harness between transmission connector and control valve body connector.
6 CHECK FOR POOR CONTACT.	Is there poor contact of ATF temperature sensor circuit?	Repair the poor contact.	Replace the TCM. Refer to TRANSMISSION CONTROL MODULE (TCM) 5AT-57, Transmission Control Module (TCM).