P0894

A760H AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM (for 4GR-FSE): P0894, P2714: Transmission Component Slipping
P2714 - Pressure Control Solenoid "D" Performance (Shift Solenoid Valve SLT)

DESCRIPTION

The linear solenoid valve (SLT) controls the transmission line pressure for smooth transmission operation based on signals from the throttle position sensor and the vehicle speed sensor. The ECM adjusts the duty ratio (*) of the SLT solenoid valve to control hydraulic line pressure coming from the primary regulator valve. Appropriate line pressure assures smooth shifting with varying engine outputs.

HINT
*: The duty ratio is the ratio of the current ON time (A) to the total of the current ON and OFF time (A + B).

Duty Ratio (%) = A / (A + B) x 100

MONITOR DESCRIPTION

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

There are two reasons that make the revolution difference.

- When the shift solenoid valve SLT remains on, oil pressure goes down and clutch engagement force decreases.

- When the shift solenoid valve remains on or off, the gear position commanded by the ECM and the actual gear position are not the same.

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

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

ALL

TYPICAL MALFUNCTION THRESHOLDS

[P0894: ON malfunction]

- When either condition below is met: OFF malfunction (A) or (B)

ON malfunction (A)

ON malfunction (B)

[P2714: ON malfunction]

- One of the following conditions is met: ON malfunction (A), (B), (C), (D), (E), (F), (G) or (H)

ON malfunction (A)

ON malfunction (B)

ON malfunction (C)

ON malfunction (D)

ON malfunction (E)

ON malfunction (F)

ON malfunction (G)

ON malfunction (H)

INSPECTION PROCEDURE

NOTICE:
Perform the universal trip to clear permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

PROCEDURE

1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0894 AND P2714)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG) position and push the Techstream main switch ON.

(c) When you use Techstream:

Select the item "Powertrain / ECT / Trouble Codes".

(d) Read the DTCs using the Techstream.

Result:

HINT
If any other codes besides P0894 and P2714 are output, perform troubleshooting for those DTCs first.

B -- GO TO DTC CHART
A -- Continue to next step.

2. PERFORM ACTIVE TEST USING TECHSTREAM (SHIFT SOLENOID VALVE SLT)

NOTICE:
- Perform the test at the normal operating ATF (Automatic Transmission Fluid) temperature: 50 to 80°C (122 to 176°F)
- Be careful to prevent SST hose from interfering with the exhaust pipe.
- This check must be conducted after checking and adjusting engine.
- Perform under condition that A/C is OFF.

HINT
Using the Techstream to perform Active Test allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Test early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Test.

(a) Turn the engine switch off.

(b) Lift the vehicle up.

(c) Remove the test plug on the transmission case center right side and connect SST.

SST : 09992-00095

09992-00231

09992-00271

(d) Lower the vehicle.

(e) Fully apply the parking brake and chock the 4 wheels.

(f) Connect the Techstream to the DLC3.

(g) Start the engine.

(h) Warm up the ATF (Automatic Transmission Fluid).

(i) Measure the line pressure when the engine is idling.

(j) Turn the Techstream on.

(k) Select the item "Powertrain / ECT / Active Test".

(l) According to the display on tester, perform the "Active Test".

(m) Measure the line pressure with SST.

*: "Activate the Solenoid (SLT)" in the Active Test is performed to check the line pressure changes by connecting the SST to the automatic transmission, which is used in the HYDRAULIC TEST Hydraulic Test as well.

HINT
The pressure values in Active Test and HYDRAULIC TEST are different from each other.

OK:

The line pressure changes as specified when performing the Active Test.

NG -- INSPECT SHIFT SOLENOID VALVE SLT
OK -- Continue to next step.

3. PERFORM ACTIVE TEST USING TECHSTREAM (RUNNING TEST)

HINT
Using the Techstream to perform Active Test allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Test early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Test.

(a) Warm up the engine.

(b) Turn the engine switch off.

(c) Connect the Techstream to the DLC3.

(d) Turn the engine switch on (IG) position.

(e) Turn the Techstream on.

(f) Select the item "Powertrain / ECT / Active Test".

(g) According to the display on tester, perform the "Active Test".

HINT
While driving, the shift position can be forcibly changed with the Techstream.

Comparing the shift position commanded by the Active Test with the actual shift position enables you to confirm the problem Fail-Safe Chart.

HINT
- This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.
- The 4th to 5th and 5th to 6th up-shiftings must be performed with the accelerator pedal released.
- The 6th to 5th and 5th to 4th down-shiftings must be performed with the accelerator pedal released.
- Do not operate the accelerator pedal for at least 2 seconds after shifting and do not shift successively.
- The shift position commanded by the ECM is shown in the Data List (Shift Status) display on the Techstream.
- Gear positions in the event of a solenoid valve mechanical problem:

HINT
- *1: When shift solenoid S1 is stuck ON, the vehicle cannot drive in reverse.
- *2: Neutral
- *3: When shift solenoid S4 is stuck ON, gear shifting is normal.

OK:

Gear position changes in accordance with the tester command.

OK -- INSPECT SHIFT SOLENOID VALVE SLT

B -- INSPECT SHIFT SOLENOID VALVE S2

C -- INSPECT SHIFT SOLENOID VALVE S3

D -- INSPECT SHIFT SOLENOID VALVE S4
A -- Continue to next step.

4. INSPECT SHIFT SOLENOID VALVE S1

(a) Remove the shift solenoid valve S1.