Home/Lexus/GX/Lexus GX J150 (2009-2013)/Repair manual/Automatic Trans/Automatic Transmission (Diagnostic Codes & Circuit Tests): …
Contents Wiring diagrams Section: Automatic Trans All sections

Automatic Transmission (Diagnostic Codes & Circuit Tests): Overview Lexus GX J150

Automatic Trans 7 illustrations ~4871 words

DESCRIPTION

The Park/Neutral Position (PNP) switch detects the shift lever position and sends signals to the ECM.

DTC CodeDTC Detection ConditionTrouble Area
P0705One of the following conditions is met: (A) Any 2 or more of the following signals are ON simultaneously (2-trip detection logic): P input signal N input signal NSW input signal R input signal D input signal (B) Any of the following signals is ON for 2.0 seconds or more with the shift lever in S (2-trip detection logic): P input signal N input signal NSW input signal R input signal (C) All signals are OFF simultaneously for NSW, P, R, N and D positions (2-trip detection logic).Open or short in park/neutral position switch circuit Park/neutral position switch Transmission control switch (transmission floor shift assembly) ECM

MONITOR DESCRIPTION

This DTC indicates a problem with the park/neutral position switch or the wire harness in the park/neutral position switch circuit.

The park/neutral position switch detects the shift lever position and sends a signal to the ECM.

For security, the park/neutral position switch detects the shift lever position so that the engine can be started only when the shift lever is in P or N.

The park/neutral position switch sends a signal to the ECM according to the shift lever position (P, R, N, D or S).

The ECM determines that there is a problem with the switch or related parts if it receives more than 1 position signal simultaneously. The ECM will illuminate the MIL and store the DTC.

The ATF (Automatic Transmission Fluid) temperature sensor converts the ATF temperature into a resistance value which is input into the ECM.

The ECM applies a voltage to the temperature sensor through ECM terminal THO1.

The sensor resistance changes with the ATF temperature.

One terminal of the sensor is grounded so that the sensor resistance and voltage decrease as the temperature becomes higher.

The ECM calculates the ATF temperature based on the voltage signal.

DTC CodeDTC Detection ConditionTrouble Area
P0711Either condition is met: 1. Conditions (a), (b), (c), (d), (e) and (f) are met (2-trip detection logic): (a) After the engine is stopped, 5 hours or more elapse before the engine is started. (b) 10 minutes elapse after the engine is started. (c) The vehicle is driven 4.7 km (3.0 miles) or more after the engine is started. (d) IAT is 15°C (59°F) or higher. (e) ECT is 15°C (59°F) or higher. (f) ATF temperature is below 20°C (68°F). 2. Conditions (a) and (b) are met (2-trip detection logic): (a) Engine coolant temperature is below 35°C (95°F) after the engine is started. (b) ATF temperature is 110°C (230°F) or higher when the engine coolant temperature reaches 60°C (140°F) after 10 sec. or more.Transmission wire (No. 1 ATF temperature sensor)

This DTC indicates that there is a problem with the output from the Automatic Transmission Fluid (ATF) temperature sensor and that the sensor itself is defective. The ATF temperature sensor converts the ATF temperature to an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature and detects an open or short in the ATF temperature sensor circuit or a fault in the ATF temperature sensor.

After running the vehicle for a certain period, the ATF temperature should increase. If the ATF temperature is below 20°C (68°F) after running the vehicle for a certain period, the ECM interprets this as a fault, turns on the MIL and stores the DTC.

When the ATF temperature is 110°C (230°F) or higher and the engine coolant temperature takes 10 seconds or more to reach 60°C (140°F) after a cold start, the ECM also determines this to be a fault, turns on the MIL and stores the DTC.

Refer to DTC P0711. Refer to DESCRIPTION .

DTC CodeDTC Detection ConditionTrouble Area
P0712ATF temperature sensor resistance is below 79 ohms for 0.5 sec. or more (1-trip detection logic).Short in ATF temperature sensor circuit ATF temperature sensor (No. 1 ATF temperature sensor) ECM
P0713One of the following conditions is met (1-trip detection logic): (A) 332 sec. or more have elapsed after the engine start when the engine coolant temperature or intake air temperature is -29.375°C (-20.875°F) or less, and the ATF temperature sensor resistance is higher than 156 kohms for 0.5 sec. or more. (B) 10 sec. or more have elapsed after the engine start when the engine coolant temperature and intake air temperature are higher than -29.375°C (-20.875°F), and the ATF temperature sensor resistance is higher than 156 kohms for 0.5 sec. or more.Open in ATF temperature sensor circuit ATF temperature sensor (No. 1 ATF temperature sensor) ECM

The ATF temperature sensor converts the ATF temperature to an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature and detects an open or short in the ATF temperature sensor circuit. If the resistance value of the ATF temperature sensor is below 79 ohms*1 or higher than 156 kohms*2, the ECM interprets this as a fault in the ATF temperature sensor or wiring. The ECM will illuminate the MIL and store the DTC.

HINT

  1. *1: 150°C (302°F) or higher is indicated regardless of the actual ATF temperature.
  2. *2: -40°C (-40°F) is indicated regardless of the actual ATF temperature.
  3. The ATF temperature can be checked on the Techstream display.

This sensor detects the rotation speed of the turbine which indicates the input speed of the transmission. By comparing the input turbine speed signal NT with the output speed sensor signal SP2, the ECM detects the shift timing of the gears and appropriately controls the engine torque and hydraulic pressure according to various conditions, and as a result, the gears shift smoothly.

DTC CodeDTC Detection ConditionTrouble Area
P0717All conditions are met for 5 seconds or more (1-trip detection logic): (a) Gear change is not performed. (b) Gear position is 4th, 5th or 6th (c) Transmission input shaft speed is 300 rpm or less. (d) Transmission output shaft speed is 1000 rpm or more. (e) Park/neutral position switch NSW and R input signals are OFF. (f) Shift solenoid valves and the park/neutral position switch are operating normally.Open or short in speed sensor NT circuit Speed sensor NT ECM Automatic transmission (clutch, brake, gear, etc.)

Reference: Inspect using an oscilloscope.

Check the waveform of the ECM connector.

Standard

Terminal No. (Symbol)Tool SettingConditionSpecified Condition
C30-3 (NT+) - C30-4 (NT-)1 V/DIV., 2 msec./DIV.Engine is idling (Shift lever in P or N)Refer to illustration

Scheme 399

Scheme 399

This DTC indicates that a pulse is not output from the speed sensor NT (turbine (input) speed sensor) or is output only a little. The NT terminal of the ECM detects the pulse signal from the speed sensor NT (input RPM). The ECM outputs a gear shift signal by comparing the input speed sensor NT signal with the output speed sensor SP2 signal.

While the vehicle is operating in 4th, 5th or 6th gear with the shift lever in D, if the input shaft speed is less than 300 rpm*1 although the output shaft speed is 1000 rpm or more*2, the ECM detects the trouble, illuminates the MIL and stores the DTC.

HINT

  1. *1: A pulse is not output or is irregularly output.
  2. *2: The vehicle speed is approximately 50 km/h (30 mph) or more.

The speed sensor SP2 detects the rotation speed of the transmission output shaft and sends signals to the ECM. The ECM determines the vehicle speed based on these signals. An AC voltage is generated in the speed sensor SP2 coil as the parking gear mounted on the rear planetary gear assembly rotates, and this voltage is sent to the ECM. The parking gear on the rear planetary gear is used as the timing rotor for this sensor.

The gear shift point and lock-up timing are controlled by the ECM based on the signals from this vehicle speed sensor and the throttle position sensor signal.

DTC CodeDTC Detection ConditionTrouble Area
P0722All conditions are met for 5 seconds or more continuously (2-trip detection logic): (a) No signal from speed sensor SP2 is input to the ECM while 4 pulses of the No. 1 vehicle speed sensor signal are sent. (b) Vehicle speed is 9 km/h (5.59 mph) or more. (c) Park/neutral position switch is OFF.Open or short in speed sensor SP2 circuit Speed sensor SP2 ECM Automatic transmission (clutch, brake, gear, etc.)

Reference: Inspect using an oscilloscope.

Check the waveform of the ECM connector.

Standard

Terminal No. (Symbol)Tool SettingConditionSpecified Condition
C30-9 (SP2+) - C30-10 (SP2-)2 V/DIV., 20 msec./DIVVehicle speed 20 km/h (12 mph)Refer to illustration

Scheme 400

Scheme 400

The output speed sensor SP2 monitors the output shaft speed. The ECM controls the gear shift point and lock-up timing based on the signals from the output speed sensor SP2 and throttle position sensor.

If the ECM detects no signal from the output speed sensor SP2 even while the vehicle is moving, it will conclude that there is a malfunction of the output speed sensor SP2. The ECM will illuminate the MIL and store the DTC.

The ECM uses signals from output speed sensor SP2 and input speed sensor NT to detect the actual gear position (1st, 2nd, 3rd, 4th, 5th or 6th gear). Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves, valve body and automatic transmission (clutch, brake, gear, etc.).

DTC CodeDTC Detection ConditionTrouble Area
P07296th gear shift malfunction: The ECM determines there is a malfunction when both of the following conditions are met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 5th gear, the actual gear is shifted to 5th.(b) When the ECM directs the transmission to switch to 6th gear, the actual gear is shifted to 4th.Valve body is blocked or stuck (sequence valve) Shift solenoid valve SLT remains open or closed Automatic transmission (clutch, brake, gear, etc.)

HINT

  1. Gear positions in the event of a solenoid valve mechanical problem: ECM gear shift command 1st 2nd 3rd 4th 5th 6th Actual gear position under malfunction 1st 2nd 3rd 4th 5th 4th
  2. Gear position during fail-safe operation: If any malfunction is detected, the ECM enters fail-safe mode and performs gear shifts as shown in the table below. Gear position under normal conditions 1st 2nd 3rd 4th 5th 6th Actual gear position under fail-safe mode 1st 2nd 3rd 3rd 3rd 3rd

The ECM commands gear shifts by turning the shift solenoid valves ON/OFF and switching oil pressure to the valves in the valve body.

This DTC indicates that the sequence valve is locked with the spring stretched and that shifting to 6th gear is impossible.

Shifting from 1st to 6th is performed in combination with the ON and OFF operation of shift solenoid valves SL1, SL2, S1, S2, S3, S4 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 valves to allow the vehicle to be operated safely. Refer to FAIL-SAFE CHART .

DTC CodeDTC Detection ConditionTrouble Area
P0748The ECM checks for an open or short in the shift solenoid valve SL1 circuit while driving and shifting between 4th and 5th gear (1-trip detection logic). Output signal duty equals 100%. HINT: SL1 output signal duty is less than 100% under normal conditions.Open or short in shift solenoid valve SL1 circuit Shift solenoid valve SL1 ECM

This DTC indicates an open or short in the shift solenoid valve SL1 circuit. 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 an open or short circuit, the ECM stops sending current to the open or short-circuited solenoid.

While driving and shifting between 4th and 5th gears, if the ECM detects an open or short in the shift solenoid valve SL1 circuit, the ECM determines that there is a malfunction. Refer to FAIL-SAFE CHART .

The ECM uses signals from the output shaft speed sensor and input speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th, 5th or 6th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves, valve body and automatic transmission (clutch, brake, gear, etc.).

DTC CodeDTC Detection ConditionTrouble Area
P0751S1 stuck ON malfunction*1: The ECM determines there is a malfunction when the following conditions are both met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 1st gear, the actual gear is shifted to 2nd.(b) When the ECM directs the transmission to switch to 5th gear, the actual gear is shifted to 5th.Shift solenoid valve S1 remains closed Valve body is blocked Automatic transmission (clutch, brake, gear, etc.)
P0751S1 stuck OFF malfunction*2: The ECM determines there is a malfunction when conditions (a) and (b) are met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 5th gear, the actual gear is shifted to 5th.(b) When the ECM directs the transmission to switch to 6th gear, the engine overruns (clutch slips).Shift solenoid valve S1 remains open Shift solenoid valve SLT remains open or closed Valve body is blocked No. 2 brake malfunction (driving is difficult) Automatic transmission (clutch, brake, gear, etc.)

HINT

  1. Gear positions in the event of a solenoid valve mechanical problem: ECM gear shift command 1st 2nd 3rd 4th 5th 6th *1: Actual gear position under S1 stuck ON malfunction 2nd 2nd 3rd 4th 5th 6th *2: Actual gear position under S1 stuck OFF malfunction 1st 1st 3rd 4th 5th N* N*: Neutral
  2. Gear position during fail-safe operation: If any malfunction is detected, the ECM enters fail-safe mode and performs gear shifts as shown in the table below. Gear position under normal conditions 1st 2nd 3rd 4th 5th 6th *1: Actual gear position under fail-safe mode during S1 stuck ON malfunction 2nd 2nd 3rd 4th 5th 6th *2: Actual gear position under fail-safe mode during S1 stuck OFF malfunction 1st*3 1st*3 3rd 3rd 3rd 3rd *3: Under engine braking, downshifting to 1st or 2nd gear is prohibited.

This DTC indicates a "stuck ON malfunction" or "stuck OFF malfunction" of shift solenoid valve S1.

The ECM commands gear shifts by turning the shift solenoid valves ON/OFF. When the gear position commanded by the ECM and the actual gear position are not the same, the ECM illuminates the MIL and stores the DTC.

The ECM uses signals from the output shaft speed sensor and input speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th, 5th or 6th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves, valve body and automatic transmission (clutch, brake, gear, etc.).

DTC CodeDTC Detection ConditionTrouble Area
P0756S2 stuck ON malfunction*1: Shifting to 3rd and 5th gears is impossible. The ECM determines there is a malfunction when the following conditions are both met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 5th gear, the actual gear is shifted to 6th.(b) When the ECM directs the transmission to switch to 6th gear, the actual gear is shifted to 6th.Shift solenoid valve S2 remains closed Valve body is blocked Automatic transmission (clutch, brake, gear, etc.)
P0756S2 stuck OFF malfunction*2: The vehicle starts in 3rd gear and shifting to 6th gear is impossible. The ECM determines there is a malfunction when the following conditions are both met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 1st gear, the actual gear is shifted to 3rd.(b) When the ECM directs the transmission to switch to 6th gear, the actual gear is shifted to 5th.Shift solenoid valve S2 remains open Shift solenoid valve SLT remains open or closed Valve body is blocked Automatic transmission (clutch, brake, gear, etc.)

HINT

Gear positions in the event of a solenoid valve mechanical problem

ECM gear shift command1st2nd3rd4th5th6th
*1: Actual gear position under S2 stuck ON malfunction1st2nd2nd4th6th6th
*2: Actual gear position under S2 stuck OFF malfunction3rd3rd3rd4th5th5th

This DTC indicates a "stuck ON malfunction" or "stuck OFF malfunction" of shift solenoid valve S2.

The ECM commands gear shifts by turning the shift solenoid valves ON/OFF. When the gear position commanded by the ECM and the actual gear position are not the same, the ECM illuminates the MIL and stores the DTC.

The ECM uses signals from the output shaft speed sensor and input speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th, 5th or 6th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves, valve body and automatic transmission (clutch, brake, gear, etc.).

DTC CodeDTC Detection ConditionTrouble Area
P0761S3 stuck ON malfunction*1: When the ECM directs the transmission to switch to 5th or 6th gear, the engine overruns (clutch slips). The ECM determines there is a malfunction when either of the following conditions is met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 4th gear, the actual gear is shifted to 3rd.(b) When the ECM directs the transmission to switch to 5th gear, the engine overruns (clutch slips).Shift solenoid valve S3 remains closed Shift solenoid valve SLT remains closed Valve body is blocked Automatic transmission (clutch, brake, gear, etc.)
P0761S3 stuck OFF malfunction*2: Shifting to 1st, 2nd and 3rd gears is impossible. The ECM determines there is a malfunction when the following conditions are both met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 2nd gear, the actual gear is shifted to 4th.(b) When the ECM directs the transmission to switch to 6th gear, the actual gear is shifted to 6th.Shift solenoid valve S3 remains open Valve body is blocked Automatic transmission (clutch, brake, gear, etc.)

HINT

  1. Gear positions in the event of a solenoid valve mechanical problem: ECM gear shift command 1st 2nd 3rd 4th 5th 6th *1: Actual gear position under S3 stuck ON malfunction 1st 2nd 3rd 3rd N* N* *2: Actual gear position under S3 stuck OFF malfunction 3rd 4th 4th 4th 5th 6th N*: Neutral
  2. Gear position during fail-safe operation: If any malfunction is detected, the ECM enters fail-safe mode and performs gear shifts as shown in the table below. Gear position under normal conditions 1st 2nd 3rd 4th 5th 6th *1: Actual gear position under fail-safe mode during S3 stuck ON malfunction 1st 2nd 3rd 3rd 3rd 3rd *2: Actual gear position under fail-safe mode during S3 stuck OFF malfunction 3rd 4th 4th 4th 5th 6th

This DTC indicates a "stuck ON malfunction" or "stuck OFF malfunction" of shift solenoid valve S3.

The ECM commands gear shifts by turning the shift solenoid valves ON/OFF. When the gear position commanded by the ECM and the actual gear position are not the same, the ECM illuminates the MIL and stores the DTC.

The ECM uses signals from the output shaft speed sensor and input speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th, 5th or 6th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves, valve body and automatic transmission (clutch, brake, gear, etc.).

DTC CodeDTC Detection ConditionTrouble Area
P0766S4 stuck OFF malfunction or brake control valve malfunction*: Shifting to 5th and 6th gears is impossible. The ECM determines there is a malfunction when the following conditions are both met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 5th gear, the actual gear is shifted to 4th.(b) When the ECM directs the transmission to switch to 6th gear, the actual gear is shifted to 4th.Shift solenoid valve S4 remains closed Shift solenoid valve SLT remains open or closed Valve body is blocked (brake control valve) Automatic transmission (clutch, brake, gear, etc.)
P0776SL2 stuck ON malfunction or brake control valve malfunction*: Shifting to 5th and 6th gears is impossible. The ECM determines there is a malfunction when the following conditions are both met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 5th gear, the actual gear is shifted to 4th.(b) When the ECM directs the transmission to switch to 6th gear, the actual gear is shifted to 4th.Shift solenoid valve SL2 remains closed Shift solenoid valve SLT remains open or closed Valve body is blocked (brake control valve) Automatic transmission (clutch, brake, gear, etc.)

HINT

  1. Gear positions in the event of a solenoid valve mechanical problem: ECM gear shift command 1st 2nd 3rd 4th 5th 6th *: Actual gear position under malfunction 1st 2nd 3rd 4th 4th 4th
  2. Gear position during fail-safe operation: If any malfunction is detected, the ECM enters fail-safe mode and performs gear shifts as shown in the table below. Gear position under normal conditions 1st 2nd 3rd 4th 5th 6th *: Actual gear position under fail-safe mode 1st 2nd 3rd 3rd 3rd 3rd

This DTC indicates a "stuck OFF malfunction" of shift solenoid valve S4, a "stuck ON malfunction" of shift solenoid valve SL2, or a brake control valve malfunction. The ECM commands gear shifts by turning the shift solenoid valves ON/OFF. When the gear position commanded by the ECM and the actual gear position are not the same, the ECM illuminates the MIL and stores the DTCs.

Shifting from 1st to 6th is performed in combination with the ON and OFF operation of shift solenoid valves SL1, SL2, S1, S2, S3, S4 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 valves to allow the vehicle to be operated safely. Refer to FAIL-SAFE CHART .

DTC CodeDTC Detection ConditionTrouble Area
P0778The ECM checks for an open or short in the shift solenoid valve SL2 circuit while driving and shifting gears (1-trip detection logic). Output signal duty equals 100%. HINT: SL2 output signal duty is less than 100% under normal conditions.Open or short in shift solenoid valve SL2 circuit Shift solenoid valve SL2 ECM

This DTC indicates an open or short in the shift solenoid valve SL2 circuit. 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 an open or short circuit, the ECM stops sending current to the open or short-circuited solenoid.

While driving and shifting gears, if the ECM detects an open or short in the shift solenoid valve SL2 circuit, the ECM determines there is a malfunction. Refer to FAIL-SAFE CHART .

The 1-2 shift valve performs shifting to 1st gear and other gears. When shifting to 2nd and 4th gears is impossible, or when the ECM directs the transmission to switch to 5th or 6th gear and the engine overruns (clutch slips), this DTC is stored.

DTC CodeDTC Detection ConditionTrouble Area
P0781Conditions (a) and (b), or (a) and (c) are met (2-trip detection logic): (a) When the ECM directs the transmission to switch to 2nd gear, the actual gear is shifted to 1st.(b) When the ECM directs the transmission to switch to 4th gear, the actual gear is shifted to 3rd.(c) When the ECM directs the transmission to switch to 5th gear, the engine overruns (clutch slips).Valve body is blocked or stuck (1-2 shift valve) Shift solenoid valve SLT remains open or closed Automatic transmission (clutch, brake, gear, etc.)

HINT

  1. Gear positions in the event of a solenoid valve mechanical problem: ECM gear shift command 1st 2nd 3rd 4th 5th 6th Actual gear position under malfunction 1st 1st 3rd 3rd N* N* N*: Neutral
  2. Gear position during fail-safe operation: If any malfunction is detected, the ECM enters fail-safe mode and performs gear shifts as shown in the table below.
Gear position under normal conditions1st2nd3rd4th5th6th
Actual gear position under fail-safe mode1st*1st*3rd3rd3rd3rd

1st*: Under engine braking, downshifting to 1st or 2nd gear is prohibited.

This DTC indicates that the 1-2 shift valve in the valve body is locked with the spring compressed.

The ECM commands gear shifts by turning the shift solenoid valves ON/OFF and switching oil pressure to the valves in the valve body.

The ECM calculates the "actual" transmission gear by comparing the signals from the input speed sensor (NT) and the output speed sensor (SP2). The ECM can detect many mechanical problems in the shift solenoids, valve body, transmission clutches, brakes and gears. If the ECM detects that the actual gear position and the commanded gear position are different, it will illuminate the MIL and store the DTC.

The ECM calculates the amount of heat absorbed by the friction material based on the difference in speed (clutch slippage) between the turbine and output shaft. The ECM illuminates the MIL and stores this DTC when the amount of heat absorption exceeds the specified value.

There are two causes of speed difference.

  1. When shift solenoid valve SLT remains ON, oil pressure decreases, which causes the clutch engagement force to decrease.
  2. When a shift solenoid valve remains ON or OFF, the gear position commanded by the ECM and the actual gear position are not the same.

Note. If you continue driving under these conditions, the clutch will burn out and the vehicle will no longer be drivable.

Shifting from 1st to 6th is performed in combination with the ON and OFF operation of shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR, which are controlled by the ECM. If an open or short circuit occurs in any of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valves to allow the vehicle to be operated safely. Also, the ECM stops sending current to the open or short-circuited solenoid. Refer to FAIL-SAFE CHART .

DTC CodeDTC Detection ConditionTrouble Area
P0973ECM detects a short in the solenoid valve S1 circuit 2 times when solenoid valve S1 is operated (1-trip detection logic).Short in shift solenoid valve S1 circuit Shift solenoid valve S1 ECM
P0974ECM detects an open in the solenoid valve S1 circuit 2 times when solenoid valve S1 is not operated (1-trip detection logic).Open in shift solenoid valve S1 circuit Shift solenoid valve S1 ECM

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 shift solenoid valve S1 is ON, if its resistance is 8 ohms or less, the ECM determines there is a short in the shift solenoid valve S1 circuit.

When shift solenoid valve S1 is OFF, if its resistance is 100 kohms or higher, the ECM determines there is an open in the shift solenoid valve S1 circuit. Refer to FAIL-SAFE CHART .

Shifting from 1st to 6th is performed in combination with the ON and OFF operation of shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR, which are controlled by the ECM. If an open or short circuit occurs in any of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valves to allow the vehicle to be operated safely. Also, the ECM stops sending current to the open or short-circuited solenoid. Refer to FAIL-SAFE CHART .

DTC CodeDTC Detection ConditionTrouble Area
P0976ECM detects a short in the solenoid valve S2 circuit 2 times when solenoid valve S2 is operated (1-trip detection logic).Short in shift solenoid valve S2 circuit Shift solenoid valve S2 ECM
P0977ECM detects an open in the solenoid valve S2 circuit 2 times when solenoid valve S2 is not operated (1-trip detection logic).Open in shift solenoid valve S2 circuit Shift solenoid valve S2 ECM

These DTCs indicate an open or short in the shift solenoid valve S2 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 shift solenoid valve S2 is ON, if its resistance is 8 ohms or less, the ECM determines there is a short in the shift solenoid valve S2 circuit.

When shift solenoid valve S2 is OFF, if its resistance is 100 kohms or higher, the ECM determines there is an open in the shift solenoid valve S2 circuit. Refer to FAIL-SAFE CHART .

Shifting from 1st to 6th is performed in combination with the ON and OFF operation of shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR, which are controlled by the ECM. If an open or short circuit occurs in any of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valves to allow the vehicle to be operated safely. Also, the ECM stops sending current to the open or short-circuited solenoid. Refer to FAIL-SAFE CHART .

DTC CodeDTC Detection ConditionTrouble Area
P0979ECM detects a short in the solenoid valve S3 circuit 2 times when solenoid valve S3 is operated (1-trip detection logic).Short in shift solenoid valve S3 circuit Shift solenoid valve S3 ECM
P0980ECM detects an open in the solenoid valve S3 circuit 2 times when solenoid valve S3 is not operated (1-trip detection logic).Open in shift solenoid valve S3 circuit Shift solenoid valve S3 ECM

These DTCs indicate an open or short in the shift solenoid valve S3 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 shift solenoid valve S3 is ON, if its resistance is 8 ohms or less, the ECM determines there is a short in the shift solenoid valve S3 circuit.

When shift solenoid valve S3 is OFF, if its resistance is 100 kohms or higher, the ECM determines there is an open in the shift solenoid valve S3 circuit. Refer to FAIL-SAFE CHART .

Shifting from 1st to 6th is performed in combination with the ON and OFF operation of shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR, which are controlled by the ECM. If an open or short circuit occurs in any of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valves to allow the vehicle to be operated safely. Also, the ECM stops sending current to the open or short-circuited solenoid. Refer to FAIL-SAFE CHART .

DTC CodeDTC Detection ConditionTrouble Area
P0982ECM detects a short in the solenoid valve S4 circuit 2 times when solenoid valve S4 is operated (1-trip detection logic).Short in shift solenoid valve S4 circuit Shift solenoid valve S4 ECM
P0983ECM detects an open in the solenoid valve S4 circuit 2 times when solenoid valve S4 is not operated (1-trip detection logic).Open in shift solenoid valve S4 circuit Shift solenoid valve S4 ECM

These DTCs indicate an open or short in the shift solenoid valve S4 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 shift solenoid valve S4 is ON, if its resistance is 8 ohms or less, the ECM determines there is a short in the shift solenoid valve S4 circuit.

When shift solenoid valve S4 is OFF, if its resistance is 100 kohms or higher, the ECM determines there is an open in the shift solenoid valve S4 circuit. Refer to FAIL-SAFE CHART .

Shifting from 1st to 6th is performed in combination with the ON and OFF operation of shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR, which are controlled by the ECM. If an open or short circuit occurs in any of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valves to allow the vehicle to be operated safely. Also, the ECM stops sending current to the open or short-circuited solenoid. Refer to FAIL-SAFE CHART .

DTC CodeDTC Detection ConditionTrouble Area
P0985ECM detects a short in the solenoid valve SR circuit 2 times when solenoid valve SR is operated (1-trip detection logic).Short in shift solenoid valve SR circuit Shift solenoid valve SR ECM
P0986ECM detects an open in the solenoid valve SR circuit 2 times when solenoid valve SR is not operated (1-trip detection logic).Open in shift solenoid valve SR circuit Shift solenoid valve SR ECM

These DTCs indicate an open or short in the shift solenoid valve SR 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 shift solenoid valve SR is ON, if its resistance is 8 ohms or less, the ECM determines there is a short in the shift solenoid valve SR circuit.

When shift solenoid valve SR is OFF, if its resistance is 100 kohms or higher, the ECM determines there is an open in the shift solenoid valve SR circuit. Refer to FAIL-SAFE CHART .

Refer to DTC P0894. Refer to DESCRIPTION .

DTC CodeDTC Detection ConditionTrouble Area
P2716Open or short is detected in the shift solenoid valve SLT circuit for 1 second or more while driving (1-trip detection logic).Open or short in shift solenoid valve SLT circuit Shift solenoid valve SLT ECM

When an open or short in the shift solenoid valve SLT circuit is detected, the ECM interprets this as a fault. The ECM will turn on the MIL and store the DTC.

The Automatic Transmission Fluid (ATF) temperature sensor is on the transmission, just in front of the oil cooler inlet pipeline.

If the ECM detects an abnormally high ATF temperature near this sensor, a message is displayed on the multi-information display.

HINT

  1. The temperature of the ATF easily rises when towing, climbing hills, in traffic, etc.
  2. If the ATF temperature sensor becomes short-circuited, the signal that indicates that the ATF temperature is 150°C (302°F) or higher is input into the ECM.

Vehicle conditions when the sensor is normal and when the sensor is short-circuited are indicated in the table below.

No. 2 ATF Temperature Sensor StateDetection ConditionSymptomRecovery Condition
Sensor is normalATF temperature higher than 150°C (302°F)Message is displayed on multi-information displayATF temperature below 135°C (275°F)*1
ATF temperature higher than 130°C (266°F)Shift point too highATF temperature below 110°C (230°F)
When conditions (a) and (b) are satisfied. (a) ATF temperature higher than 130°C (266°F) (b) Engine coolant temperature higher than 95°C (203°F)Lock-up in 3rd gear*2ATF temperature below 110°C (230°F)*1 and engine coolant temperature higher than 95°C (203°F)
Sensor is short-circuitedAny conditionsMessage is displayed on multi-information display Shift point too highSymptoms persist
Engine coolant temperature higher than 95°C (203°F)Lock-up in 3rd gear*2Symptoms persist

HINT

*1: When the ATF is normal, it decreases to below 135°C (275°F) within 5 minutes with the shift lever in P or N in an idling state.

*2: When ATF temperature is normal, transmission lock-up occurs in 5th or 6th gear with the shift lever in D or with the S6 range selected, in 5th gear with the S5 range selected, and in 4th gear with the S4 range selected.

DTC CodeDTC Detection ConditionTrouble Area
P2742No. 2 ATF temperature sensor resistance is below 25 ohms (0.046 V) for 0.5 seconds or more (1-trip detection logic).Short in No. 2 ATF temperature sensor circuit Transmission wire (No. 2 ATF temperature sensor) ECM
P2743One of the following conditions is met (1-trip detection logic): (A) 15 min. or more have elapsed after the engine start when the engine coolant temperature or intake air temperature is -29.375°C (-20.875°F) or less, and the ATF temperature sensor resistance is higher than 156 kohms (4.915 V) for 0.5 sec. or more. (B) 10 sec. or more have elapsed after the engine start when the engine coolant temperature and intake air temperature are higher than -29.375°C (-20.875°F), and the ATF temperature sensor resistance is higher than 156 kohms (4.915 V) for 0.5 sec. or more.Open in No. 2 ATF temperature sensor circuit Transmission wire (No. 2 ATF temperature sensor) ECM

The ATF temperature sensor converts the ATF temperature into an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature, and the ECM detects an open or short in the ATF temperature circuit. If the resistance value of the ATF temperature sensor is below 25 ohms*1 or higher than 156 kohms*2, the ECM interprets this as a fault in the ATF sensor or wiring. The ECM will display a message on the multi-information display and store the DTC.

HINT

  1. *1: 150°C (302°F) or higher is indicated regardless of the actual ATF temperature.
  2. *2: -40°C (-40°F) is indicated regardless of the actual ATF temperature.
  3. The ATF temperature can be checked on the Techstream display.

The ECM uses the signals from the throttle position sensor, air flow meter, turbine (input) speed sensor, output speed sensor and crankshaft position sensor to monitor the engagement condition of the lock-up clutch.

Scheme 401

Scheme 401: DESCRIPTION

Then the ECM compares the engagement condition of the lock-up clutch with the lock-up schedule in the ECM memory to detect mechanical problems of shift solenoid valve SLU, the valve body and torque converter clutch.

DTC CodeDTC Detection ConditionTrouble Area
P2757Lock-up does not occur when driving in the lock-up range (normal driving at 80 km/h (50 mph)), or lock-up remains ON in the lock-up OFF range (2-trip detection logic).Shift solenoid valve SLU remains open or closed Valve body is blocked Shift solenoid valve SLU Torque converter clutch Automatic transmission (clutch, brake, gear, etc.) Line pressure is too low

Torque converter lock-up is controlled by the ECM based on the turbine (input) speed sensor NT, output speed sensor SP2, engine speed, engine load, engine temperature, vehicle speed, transmission temperature and gear selection. The ECM determines the lock-up status of the torque converter by comparing the engine speed (NE) to the input turbine speed (NT). The ECM calculates the actual transmission gear by comparing input turbine speed (NT) to the output shaft speed (SP2). When conditions are appropriate, the ECM requests lock-up by applying control voltage to shift solenoid SLU. When shift solenoid valve SLU is turned ON, it applies pressure to the lock-up relay valve and locks the torque converter clutch.

If the ECM detects no lock-up after lock-up has been requested or if it detects lock-up when it is not requested, the ECM interprets this as a fault in shift solenoid valve SLU or lock-up system performance.

The ECM will illuminate the MIL and store the DTC.

Example

When one of the following conditions is met, the system determines that there is a malfunction.

  1. There is a difference in speed between the input side (engine speed) and output side (input turbine speed) of the torque converter when the ECM commands lock-up ON. The engine speed is at least 70 rpm more than the input turbine speed.
  2. There is no difference in rotation between the input side (engine speed) and output side (input turbine speed) of the torque converter when the ECM commands lock-up OFF. The difference between the engine speed and input turbine speed is less than 35 rpm.

The amount of current flow to the solenoid is controlled by the ECM. During the lock-up operation, if the current increases, the lock-up hydraulic pressure increases.

DTC CodeDTC Detection ConditionTrouble Area
P2759Open or short is detected in the shift solenoid valve SLU circuit for 1 second or more while driving (1-trip detection logic).Open or short in shift solenoid valve SLU circuit Shift solenoid valve SLU ECM

When an open or short in the shift solenoid valve SLU circuit is detected, the ECM determines that there is a malfunction. The ECM will illuminate the MIL and store the DTC.

The ECM detects the signal from the transfer L4 position switch.

This DTC indicates that the transfer L4 position switch remains on.

DTC CodeDTC Detection ConditionTrouble Area
P2772Transfer L4 position switch remains on while the vehicle is being driven under the following conditions for 1.8 sec. or more (1-trip detection logic): (a) Output shaft speed is between 1000 and 3000 rpm. (b) Transfer position switch is in H4.Short in transfer L4 position switch circuit Transfer system ECM

The ECM monitors the transfer-case L4 position switch to determine when the transfer-case L4 gears are engaged. If the L4 position switch indicates that the transfer-case L4 gears are engaged under the following conditions, the ECM will conclude that there is a malfunction of the L4 position switch, illuminate the MIL and store the DTC

  1. The transfer-case shifter is in the "H4" position.
  2. The transfer-case output shaft speed is between 1000 and 3000 rpm.
  3. The specified time period has elapsed.

After moving the shift lever to S, it is possible to switch the shift range between "1" (S1 range) and "6" (S6 range) using the transmission control switch.

Shifting to "+" once raises the shift range by one, and shifting to "-" once lowers the shift range by one.

Scheme 402

Scheme 402: WIRING DIAGRAM

Scheme 403

Scheme 403: PROCEDURE

Scheme 404

Scheme 404

Scheme 405

Scheme 405
  1. INSPECT TRANSMISSION CONTROL SWITCH Disconnect the G36 transmission control switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 3 (IG) - 7 (S) Shift lever in S, "+" or "-" Below 1 ohms 2 (SFTU) - 5 (E) Shift lever held in "+" (Up-shift) Below 1 ohms 1 (SFTD) - 5 (E) Shift lever held in "-" (Down-shift) Below 1 ohms 3 (IG) - 7 (S) Shift lever not in S, "+" or "-" 10 kohms or higher 2 (SFTU) - 5 (E) Shift lever in S 10 kohms or higher 1 (SFTD) - 5 (E) Shift lever in S 10 kohms or higher TEXT IN ILLUSTRATION *a Component without harness connected (Transmission Control Switch) NG --> See step 5 OK: Go to next step
  2. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - BATTERY, BODY GROUND) Disconnect the G36 transmission control switch connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Switch Condition Specified Condition G36-3 (IG) - Body ground Engine switch on (IG) 11 to 14 V Engine switch off Below 1 V Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition G36-5 (E) - Body ground Always Below 1 ohms TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Transmission Control Switch) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
  3. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - ECM) Disconnect the G45 ECM connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition G45-24 (S) - Body ground Engine switch on (IG) Shift lever in S, "+" or "-" 11 to 14 V Engine switch on (IG) Shift lever not in S, "+" or "-" Below 1 V Turn the engine switch off. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition G45-16 (SFTU) - Body ground Shift lever held in "+" (Up-shift) Below 1 ohms G45-22 (SFTD) - Body ground Shift lever held in "-" (Down-shift) Below 1 ohms G45-16 (SFTU) - Body ground Shift lever in S 10 kohms or higher G45-22 (SFTD) - Body ground Shift lever in S 10 kohms or higher TEXT IN ILLUSTRATION *a Front view of wire harness connector (to ECM) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 4
  4. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(ref-524128-S35672513712013012800000)
  5. REPLACE TRANSMISSION CONTROL SWITCH (TRANSMISSION FLOOR SHIFT ASSEMBLY). Refer to «REMOVAL»(ref-524256-S12787879912013012800000)