Dtc P0973/62 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)


DESCRIPTION

MONITOR DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE S1/S2)

CHECK WIRE HARNESS (SHIFT SOLENOID VALVE S1/S2 - TCM)

INSPECT SHIFT SOLENOID VALVE S1/S2

DTC P0973/62 Shift Solenoid "A" Control Circuit Low (Shift Solenoid Valve S1)

DTC P0974/62 Shift Solenoid "A" Control Circuit High (Shift Solenoid Valve S1)

DTC P0976/63 Shift Solenoid "B" Control Circuit Low (Shift Solenoid Valve S2)

DTC P0977/63 Shift Solenoid "B" Control Circuit High (Shift Solenoid Valve S2)


DESCRIPTION

Shifting from 1st to O/D is performed in combination with the on and off operation of the shift solenoid valves S1 and S2 controlled by the TCM. If an open or short circuit occurs in either of the shift solenoid valves, the TCM controls the remaining normal shift solenoid valve to allow the vehicle to be operated safely (fail-safe function).
Fail-safe function:
If either of the shift solenoid valve circuits develops an open or short circuit, the TCM turns the other shift solenoid on and off to shift to the gear positions shown in the table below. The TCM also turns the shift solenoid valve SL off at the same time. If both solenoids are malfunctioning, electronic hydraulic control does not operate and must be performed manually. Manual shifting as shown in the following table must be performed.
In case of a short circuit, the TCM stops sending current to the circuit.

Position
Normal
Shift Solenoid Valve S1 Malfunctioning
Shift Solenoid Valve S2 Malfunctioning
Both Solenoids Malfunctioning
Solenoid valve
Gear
Solenoid valve
Gear
Solenoid valve
Gear
Gear when shift lever is manually operated
S1
S2
S1
S2
S1
S2
D
ON
OFF
1st
X
OFF
O/D
ON
X
1st
O/D
ON
ON
2nd
X
ON
3rd
ON
X
1st
O/D
OFF
ON
3rd
X
ON
3rd
OFF
X
O/D
O/D
OFF
OFF
O/D
X
OFF
O/D
OFF
X
O/D
O/D
3
ON
OFF
1st
X
OFF
O/D
ON
X
1st
O/D
ON
ON
2nd
X
ON
3rd
ON
X
1st
O/D
OFF
ON
3rd
X
ON
3rd
OFF
X
3rd
O/D
2
ON
OFF
1st
X
ON
3rd
ON
X
1st
3rd
ON
ON
2nd
X
ON
3rd
OFF
X
3rd
3rd
L
ON
OFF
1st
X
OFF
O/D
ON
X
1st
1st
HINT:
X: Malfunction

DTC Code
DTC Detection Condition
Trouble Area
P0973/62
TCM detects short in solenoid valve S1 circuit 4 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. TCM
P0974/62
TCM detects open in solenoid valve S1 circuit 4 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. TCM
P0976/63
TCM detects short in solenoid valve S2 circuit 4 times when solenoid valve S2 is operated (1 trip detection logic)
  1. Short in shift solenoid valve S2 circuit
  2. Shift solenoid valve S2
  3. TCM
P0977/63
TCM detects open in solenoid valve S2 circuit 4 times when solenoid valve S2 is not operated (1 trip detection logic)
  1. Open in shift solenoid valve S2 circuit
  2. Shift solenoid valve S2
  3. TCM

MONITOR DESCRIPTION

The TCM controls gear shift by turning the shift solenoid valves on/off. When there is an open or short circuit in any shift solenoid valve circuit, the TCM detects the problem, illuminates the MIL and stores a DTC.
The TCM performs the fail-safe function and turns the normally functioning shift solenoid valve on/off.
In case of an open or short circuit, the TCM stops sending current to the circuit.

WIRING DIAGRAM


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340F Automatic Transmission.Automatic Transmission System. Dtc P0973/62 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)


INSPECTION PROCEDURE

1.INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE S1/S2)


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340F Automatic Transmission.Automatic Transmission System. Dtc P0973/62 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)

  1. Disconnect the E1 wire connector.

  1. Measure the resistance of the transmission wire.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    4 (S1) - Body ground
    		20°C (68°F)
    		11 to 15 Ω
    8 (S2) - Body ground
    		20°C (68°F)
    		11 to 15 Ω


NG
Go to step 3
OK


2.CHECK WIRE HARNESS (SHIFT SOLENOID VALVE S1/S2 - TCM)


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340F Automatic Transmission.Automatic Transmission System. Dtc P0973/62 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)

  1. Disconnect the T19 TCM connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    T19-18 (S1) - Body ground
    		20°C (68°F)
    		11 to 15 Ω
    T19-17 (S2) - Body ground
    		20°C (68°F)
    		11 to 15 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE TCM

3.INSPECT SHIFT SOLENOID VALVE S1/S2
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340F Automatic Transmission.Automatic Transmission System. Dtc P0973/62 Shift Solenoid A Control Circuit Low (Shift Solenoid Valve S1)

  1. Remove the shift solenoid valve S1/S2.

  1. Measure the resistance between the solenoid valve terminal and solenoid valve body.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    Shift solenoid valve S1 connector terminal - Shift solenoid valve S1 body
    		20°C (68°F)
    		11 to 15 Ω
    Shift solenoid valve S2 connector terminal - Shift solenoid valve S2 body
    		20°C (68°F)
    		11 to 15 Ω

  1. Connect the battery's positive (+) lead to the terminal of the solenoid connector, and the negative (-) lead to the solenoid body.

  1. Check the operating noise of the solenoid valve.

    OK:
    Solenoid makes operating noise.


NG
REPLACE SHIFT SOLENOID VALVE S1/S2
OK

REPLACE TRANSMISSION WIRE