DESCRIPTION
Shift solenoid valve SLT controls the transmission line pressure for smooth transmission operation based on signals from the throttle position sensor and vehicle speed sensor. The ECM adjusts the current to shift solenoid valve SLT to control hydraulic line pressure coming from the primary regulator valve. Appropriate line pressure assures smooth shifting with varying engine outputs.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory |
|---|---|---|---|---|---|
| P2714 | Pressure Control Solenoid "D" Performance (Shift Solenoid Valve SLT) | The ECM detects a malfunction in shift solenoid valve SLT (ON side) according to the difference in speed between the turbine and output shaft, and also by the ATF pressure (2-trip detection logic). |
|
Comes on | DTC stored |
MONITOR DESCRIPTION
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 turns on the MIL and stores this DTC when the amount of heat absorption exceeds the specified value.
When shift solenoid valve SLT remains on, the line pressure goes down and clutch engagement force decreases.
Note
If driving continues under these conditions, clutches will burn out and the vehicle will no longer be drivable.
CAUTION / NOTICE / HINT
Note
Perform registration and/or initialization when parts related to the automatic transaxle are replaced.
PROCEDURE
CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P2714)
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the DTCs using the GTS.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
If shift solenoid valve SLT is stuck on, DTCs for several shift solenoid valves including the malfunctioning shift solenoid valve will be stored.
| A |
|
GO TO STEP 4 Click here |
| B |
|
PERFORM ACTIVE TEST USING GTS (SHIFT SOLENOID VALVE SLT)
Note
Perform the test while the ATF temperature is 50 to 80°C (122 to 176°F).
Be careful to prevent the hose of SST from interfering with the exhaust pipe.
This check must be conducted after checking and confirming that the engine is normal.
Perform the test with the A/C off.
Tech Tips
Using the GTS to perform Active Tests 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 Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests.
Remove the test plug from the transaxle case and connect SST.
Connect the GTS to the DLC3.
Start the engine and warm it up.
Measure the line pressure when the engine is idling.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test.
According to the display on the GTS, perform the Active Test.
Measure the line pressure with SST.
| Tester Display | Measurement Item | Control Range | Diagnostic Note |
|---|---|---|---|
| Activate the Solenoid (SLT) | Operate shift solenoid valve SLT and raise line pressure | ON or OFF Tech Tips ON: No action (normal operation) OFF: Line pressure up (When Active Test "Activate the Solenoid (SLT)" is performed, ECM commands shift solenoid valve SLT to turn off). |
[Vehicle Condition]
|
| Tester Display |
|---|
| Activate the Solenoid (SLT) |
Tech Tips
Activate the Solenoid (SLT) in the Active Test is performed to confirm that the line pressure changes. The line pressure changes are confirmed using the same SST that is used for the Hydraulic Test.
Note that the pressure readings for the Active Test and Hydraulic Test are different.
| OK |
|---|
| The line pressure changes as specified when performing the Active Test. |
| Result | |||
|---|---|---|---|
|
| NG |
|
GO TO STEP 4 Click here |
| OK |
|
PERFORM ACTIVE TEST USING GTS (DRIVING TEST)
Note
This test should always be performed with at least 2 people.
Warm up the engine.
Turn the ignition switch off.
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test.
According to the display on the GTS, perform the Active Test.
Tech Tips
Comparing the gear commanded by the Active Test with the actual gear enables confirmation of the problem.
The gear commanded by the ECM is shown in the Data List / Shift Status display on the GTS.
| Tester Display | Measurement Item | Control Range | Diagnostic Note |
|---|---|---|---|
| Control the Shift Position | Operate the shift solenoid valves and set each shift position |
|
Can be used to check the operation of the shift solenoid valves. A 10-second interval is required between gear changes. Do not down-shift at high speeds. Doing so will damage the automatic transaxle. [Vehicle Condition] 50 km/h (30 mph) or less |
| Active Test Display |
|---|
| Control the Shift Position |
| Data List Display |
|---|
| Shift Status |
Note
This test can be conducted when the vehicle is stopped.
When shifting gears using the Active Test function, do not operate the accelerator pedal for 2 seconds before and after shifting gears.
Check the vehicle speed and the gear when the engine speed is 1000 rpm.
Tech Tips
Because the torque converter has not engaged, it may be difficult to obtain the speeds specified in 4th, 5th, and 6th gear, however a difference of speed should still be evident following each gear change.
| Standard | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Compare the ECM commanded gear and the actual gear.
| Result | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Tech Tips
*1: Neutral
*2: If shift solenoid valve SLT is stuck on, the line pressure will be low. Therefore, the amount of torque that can be transmitted by each gear is less than the normal limit. When the engine power exceeds this lowered limit, the engine speed will increase freely.
*3: When shift solenoid valve SLT is stuck off, gear shifting is normal.
| A |
|
GO TO DTC P0746 Click here |
| B |
|
GO TO DTC P0776 Click here |
| C |
|
GO TO DTC P0796 Click here |
| D |
|
GO TO DTC P2808 Click here |
| E |
|
INSPECT SHIFT SOLENOID VALVE SLT
| *1 | Shift Solenoid Valve SLT |
Remove shift solenoid valve SLT.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
Apply 12 V battery voltage to the shift solenoid valve and check that the valve moves and makes an operating noise.
| OK | ||||
|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE SHIFT SOLENOID VALVE SLT Click here |
| OK |
|
INSPECT TRANSMISSION VALVE BODY ASSEMBLY
Check the transmission valve body assembly.
| OK |
|---|
| There are no foreign objects on any valve. |
| Result | |||
|---|---|---|---|
|
| OK |
|
REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSEMBLY Click here |
| NG |
|
REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY Click here |