DTC P0973: Shift Solenoid "A" Control Circuit Low (Shift Solenoid Valve S1); DTC P0974: Shift Solenoid "A" Control Circuit High (Shift Solenoid Valve S1); DTC P0976: Shift Solenoid "B" Control Circuit Low (Shift Solenoid Valve S2); DTC P0977: Shift Solenoid "B" Control Circuit High (Shift Solenoid Valve S2); DTC P0979: Shift Solenoid "C" Control Circuit Low (Shift Solenoid Valve S3); DTC P0980: Shift Solenoid "C" Control Circuit High (Shift Solenoid Valve S3): Wiring Diagram
WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.