P0973

DTC P0973 Shift Solenoid "A" Control Circuit Low (Shift Solenoid Valve S1)
DTC P0974 Shift Solenoid "A" Control Circuit High (Shift Solenoid Valve S1)

DESCRIPTION
Shifting from 1st to O/D is performed in combination with the ON and OFF operation of the shift solenoid valve S1 and S2 controlled by the ECM. If an open or short circuit occurs in either of the solenoid valves, the ECM controls the remaining normal solenoid valve to allow the vehicle to be operated safely.

Fail-safe function:
If either of the solenoid valve circuits develops an open or short, the ECM turns the other solenoid valve ON and OFF to shift to the gear positions shown in the table. The ECM also turns the shift solenoid valve ST OFF at the same time. If both solenoids are malfunctioning, hydraulic control cannot be performed electronically and must be done manually.

Manual shifting as shown in the table must be done. In case of a short circuit, the ECM stops sending the current to the short circuited solenoid.

P0973-P0974:

MONITOR DESCRIPTION
The ECM commands gear shifts by turning the shift solenoid valves ON/OFF. When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem, illuminates the MIL and stores the DTC. Also, the ECM performs the fail-safe function and turns the other normal shift solenoid valves ON/OFF. In case of a short circuit, the ECM stop sending the current to the short circuited solenoid.

MONITOR STRATEGY