DTC P0712 Transmission Fluid Temperature Sensor Circuit Low Input

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

DTC DETECTING CONDITION:

Input signal circuit to ATF temperature sensor is open or shorted.

TROUBLE SYMPTOM:

Excessive shift shock

WIRING DIAGRAM:

Fig 1: ATF Temperature Sensor - Wiring Diagram

RESISTANCE CHART

Step	Check	Yes	No
1 CHECK HARNESS CONNECTOR BETWEEN TCM AND ATF TEMPERATURE SENSOR. Turn the ignition switch to OFF. Disconnect the connector from transmission and TCM. Measure the resistance of harness between TCM and transmission connector. Connector & terminal (B54) No. 21 - (B11) No. 11:	Is the resistance less than 1 Ω?	Go to step 2.	Repair the open circuit of harness between TCM and transmission connector.
2 CHECK HARNESS CONNECTOR BETWEEN TCM AND ATF TEMPERATURE SENSOR. Measure the resistance of harness between TCM and transmission connector. Connector & terminal (B54) No. 9 - (B11) No. 15:	Is the resistance less than 1 Ω?	Go to step 3.	Repair the open circuit of harness between TCM and transmission connector.
3 CHECK ATF TEMPERATURE SENSOR. Turn the ignition switch to OFF. Connect the connectors to transmission and TCM. Turn the ignition switch to ON and start engine. Warm-up the transmission until the ATF temperature reaches to 80°C (176°F). NOTE: If the ambient temperature is below 0°C (32°F), drive the vehicle until the ATF reaches its operating temperature. Disconnect the connector from transmission. Measure the resistance between transmission connector terminals. Connector & terminal (T4) No. 11 - No. 15:	Is the resistance between 300 - 800 Ω?	Go to step 4.	Go to step 7.
4 CHECK ATF TEMPERATURE SENSOR. Measure the resistance between transmission connector terminals. Connector & terminal (T4) No. 11 - No. 15:	Does the resistance value increase while the ATF temperature decreases?	Go to step 5.	Go to step 7.
5 CHECK INPUT SIGNAL FOR TCM USING SUBARU SELECT MONITOR. Connect the connector to transmission. Connect the Subaru Select Monitor to the data link connector. Turn the ignition switch to ON (engine OFF). Read the data of ATF temperature using Subaru Select Monitor.	Does the ATF temperature gradually decrease?	Even if the SPORT indicator light is blinking, the circuit is in normal condition at this time. A temporary poor contact of connector or harness may be the cause. Repair the harness and poor contact of ATF temperature sensor and transmission connector.	Go to step 6.
6 CHECK POOR CONTACT.	Is there poor contact in ATF temperature sensor circuit?	Repair the poor contact.	Replace the TCM. < Ref. to TRANSMISSION CONTROL MODULE (TCM) . >
7 CHECK HARNESS CONNECTOR BETWEEN TRANSMISSION AND ATF TEMPERATURE SENSOR. Turn the ignition switch to OFF. Disconnect the connector from transmission. Remove the transmission connector from bracket. Lift up the vehicle and support with rigid racks. NOTE: Raise all wheels off the floor. Drain the automatic transmission fluid. CAUTION: Do not drain ATF until it cools down. Remove the oil pan, and disconnect the control valve connector. Measure the resistance of harness between ATF temperature sensor and transmission connector. Connector & terminal (T4) No. 11 - (AT11) No. 1:	Is the resistance less than 1 Ω?	Go to step 8.	Repair the open circuit of harness between ATF temperature sensor and transmission connector.
8 CHECK HARNESS CONNECTOR BETWEEN TRANSMISSION AND ATF TEMPERATURE SENSOR. Measure the resistance of harness between ATF temperature sensor and transmission connector. Connector & terminal (T4) No. 15 - (AT11) No. 3:	Is the resistance less than 1 Ω?	Go to step 9.	Repair the open circuit of harness between ATF temperature sensor and transmission connector.
9 CHECK HARNESS CONNECTOR BETWEEN TRANSMISSION AND ATF TEMPERATURE SENSOR. Measure the resistance of harness between transmission connector and transmission ground. Connector & terminal (T4) No. 11 - Transmission ground:	Is the resistance more than 1 MΩ?	Go to step 10.	Repair the short circuit of harness between ATF temperature sensor and transmission connector.
10 CHECK HARNESS CONNECTOR BETWEEN TRANSMISSION AND ATF TEMPERATURE SENSOR. Measure the resistance of harness between transmission connector and transmission ground. Connector & terminal (T4) No. 15 - Transmission ground:	Is the resistance more than 1 MΩ?	Replace the control valve body. < Ref. to CONTROL VALVE BODY . >	Repair the short circuit of harness between ATF temperature sensor and transmission connector.