DTC P0766 Shift Solenoid "D" Performance Or Stuck Off: Wiring Diagram

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

AT Control System. Refer to appropriate SYSTEM WIRING DIAGRAM article.

Fig 1: AT Control System - Wiring Diagram (Shift Solenoid "D")

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTIC PROCEDURE

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 (B54) No. 22 - Chassis ground: (B54) No. 23 - Chassis ground: (B55) No. 1 - (B11) No. 16: (B55) No. 22 - (B11) No. 10:	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 BODY HARNESS. Measure the resistance of harness between TCM connector and body harness. Connector & terminal (B55) No. 22 - Chassis ground:	Is the resistance 1 MΩ or more?	Go to step 3 .	Repair the short circuit of harness between TCM and transmission connector.
3 CHECK INPUT SIGNAL FOR TCM. Connect all connectors. Turn the ignition switch to ON. Read the data of «D/C Fluid Pressure» using Subaru Select Monitor.	Is "OFF" displayed?	Go to step 4 .	Go to step 6 .
4 CHECK INPUT SIGNAL FOR TCM. Turn the ignition switch to OFF. Start the engine. Shift to 2nd speed of manual mode and depress the brake with checking current gear position using Subaru Select Monitor. Read the data of «D/C Fluid Pressure» using Subaru Select Monitor.	Is "ON" displayed?	Check for poor contact of harness in the solenoid output and oil pressure SW input, and repair the defective part.	Go to step 5 .
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. 10 - (T10) No. 9: (T4) No. 16 - (T11) No. 4:	Is the resistance less than 1 Ω?	Replace the control valve body. Refer to CONTROL VALVE BODY .	Replace the transmission harness assembly.
6 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 ground and control valve body connector. Connector & terminal (T10) No. 9 - Transmission ground:	Is the resistance 1 MΩ or more?	Replace the control valve body. Refer to CONTROL VALVE BODY .	Replace the transmission harness assembly.