Dtc P0973 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)


DESCRIPTION

MONITOR DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE S1)

CHECK WIRE HARNESS (TRANSMISSION WIRE - ECM)

INSPECT SHIFT SOLENOID VALVE S1

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 5th is performed in combination with the ON and OFF operation of the shift solenoid valves SL1, SL2, S1, S2 and SR, which are controlled by the ECM. If an open or short circuit occurs in the shift solenoid valves, the ECM controls the remaining normal shift solenoid valve to allow the vehicle to be operated safely (Toyota Fortuner RM000000O8L0B4X.html).

DTC Code
DTC Detection Condition
Trouble Area
P0973
ECM detects short in solenoid valve S1 circuit 2 times when solenoid valve S1 is operated (1 trip detection logic)
  1. Short in shift solenoid valve S1 circuit
  2. Shift solenoid valve S1
  3. ECM
P0974
ECM detects open in solenoid valve S1 circuit 2 times when solenoid valve S1 is not operated (1 trip detection logic)
  1. Open in shift solenoid valve S1 circuit
  2. Shift solenoid valve S1
  3. ECM

MONITOR DESCRIPTION

These DTCs indicate an open or short in the shift solenoid valve S1 circuit. 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. When the shift solenoid valve S1 is ON, if resistance is 8 Ω or less, the ECM determines that there is a short in the shift solenoid valve S1 circuit.
When the shift solenoid valve S1 is OFF, if resistance is 100 kΩ or more, the ECM determines that there is an open in the shift solenoid valve S1 circuit (Toyota Fortuner RM000000O8L0B4X.html).

WIRING DIAGRAM


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A750E Automatic Transmission.Automatic Transmission System. Dtc P0973 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)


INSPECTION PROCEDURE


HINT:
The shift solenoid valve S1 turns ON/OFF normally when the shift lever is on D:

ECM gear shift command
1st
2nd
3rd
4th
5th
Shift solenoid valve S1
ON
ON
OFF
OFF
OFF
1.INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE S1)


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A750E Automatic Transmission.Automatic Transmission System. Dtc P0973 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)

  1. Disconnect the E1 wire connector.

  1. Measure the resistance of the wire connector.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    8 (S1) - Body ground
    		20°C (68°F)
    		11 to 15 Ω


NG
Go to step 3
OK


2.CHECK WIRE HARNESS (TRANSMISSION WIRE - ECM)


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A750E Automatic Transmission.Automatic Transmission System. Dtc P0973 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)

  1. Disconnect the E16 ECM connector.

  1. Measure the resistance of the wire harness side connector.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    E16-11 (S1) - Body ground
    		20°C (68°F)
    		11 to 15 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ECM

3.INSPECT SHIFT SOLENOID VALVE S1
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A750E Automatic Transmission.Automatic Transmission System. Dtc P0973 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)

  1. Remove the shift solenoid valve SL1.

  1. Measure the resistance of the solenoid valve.

    Standard resistance:
    11 to 15 Ω at 20°C (68°F)

  1. Connect the battery's positive (+) lead to the terminal of the solenoid valve connector, and the negative (-) lead to the solenoid body. Then check that the valve moves and makes an operating noise.

    OK:
    Valve moves and makes operating noise.


NG
REPLACE SHIFT SOLENOID VALVE S1
OK

REPAIR OR REPLACE TRANSMISSION WIRE