- Shift solenoid valve SLT remains open or closed
- Shift solenoid valve S1, S2, SR, SL1 or SL2 remains open or closed
- 1-2 shift valve is stuck
- Valve body is blocked
- Automatic transmission (clutch, brake or gear, etc.)
| Last Modified: 7-3-2017 | 6.8:8.0.40 | Doc ID: RM000000W83037X |
| Model Year Start: 2007 | Model: LX470 | Prod Date Range: [08/2006 - ] |
| Title: A750F AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM: P0894,P2714; Transmission Component Slipping; 2007 MY LX470 [08/2006 - ] | ||
|
DTC |
P0894 |
Transmission Component Slipping |
|
DTC |
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
|
DTC No. |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
P0894 |
ECM detects a malfunction on SLT, S1, S2, SR, SL1, SL2 or 1-2 shift solenoid valve according to the revolution difference of the turbine and the output shaft, and also by the oil pressure. (2-trip detection logic) |
|
|
P2714 |
ECM detects a malfunction on SLT (ON side) according to the revolution difference of the turbine and the output shaft, and also by the oil pressure. (2-trip detection logic) |
|
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 turns on the MIL and outputs this DTC when the amount of heat absorption exceeds the specified value.
When the shift solenoid valve SLT, SL2, S1 or S2 remains on, or the shift solenoid valve SL1 or SR remains off, oil pressure goes down and clutch engagement force decreases.
NOTICE:
If you continue driving under these conditions, the clutch will burn out and the vehicle will no longer be drivable.
MONITOR STRATEGY
|
Related DTCs |
P0894: Automatic transmission slip malfunction P2714: Shift solenoid valve SLT/ON malfunction |
|
Required sensors/Components |
Shift solenoid valve SLT, Valve body, ATF temperature sensor, Speed sensor (NT), Speed sensor (NO) |
|
Frequency of operation |
Continuous |
|
Duration |
P0894 ON malfunction (A): Immediate P0894 ON malfunction (B): 0.4 sec. P2714: Immediate |
|
MIL operation |
2 driving cycles |
|
Sequence of operation |
None |
TYPICAL ENABLING CONDITIONS
All
|
The monitor will run whenever this DTC is not present. |
None |
|
Turbine speed sensor (NT) circuit |
Not circuit malfunction |
|
Output speed sensor (NO) circuit |
Not circuit malfunction |
|
TFT temperature sensor circuit |
Not circuit malfunction |
|
Shift solenoid valve S1 circuit |
Not circuit malfunction |
|
Shift solenoid valve S2 circuit |
Not circuit malfunction |
|
Shift solenoid valve SR circuit |
Not circuit malfunction |
|
Shift solenoid valve SL1 circuit |
Not circuit malfunction |
|
Shift solenoid valve SL2 circuit |
Not circuit malfunction |
|
Shift solenoid valve SLT circuit |
Not circuit malfunction |
|
ECT (Engine Coolant Temperature) sensor circuit |
Not circuit malfunction |
|
KCS sensor circuit |
Not circuit malfunction |
|
ETCS (Electric Throttle Control System) |
Not system down |
|
Transmission range |
"D" |
|
ECT |
40°C (104°F) or more |
|
Spark advance from Max. retard timing by KCS control |
0° crankshaft angle or more |
|
Engine |
Starting |
|
Transfer range |
"High" *1 |
|
TFT temperature |
10°C (50°F) or more |
Transfer range "HIGH" *1 (This condition is applied only 4WD)
*1: Following conditions met|
Vehicle speed sensor circuit |
Not circuit malfunction |
|
Output shaft speed sensor circuit |
Not circuit malfunction |
|
Transfer output speed |
143 rpm or more |
|
NO/NOtf (Transfer input speed/Transfer output speed) |
0.9 to 1.1 |
TYPICAL MALFUNCTION THRESHOLDS
[P0894: ON malfunction]
- When either condition below is met: OFF malfunction (A) or (B)
ON malfunction (A)
|
Summation of C1 clutch heat generations |
Specified value |
ON malfunction (B)
|
Summation of C2 clutch heat generations |
Specified value |
|
Actual gear for SLT fail judgment |
Not determined |
[P2714: ON malfunction]
- One of the following conditions is met: ON malfunction (A), (B), (C), (D), (E), (F) or (G)
ON malfunction (A)
|
Summation of C1 clutch heat generations |
Specified value |
ON malfunction (B)
|
Shift solenoid valve S1 ON malfunction |
Detected |
ON malfunction (C)
|
Shift solenoid valve S2 ON malfunction |
Detected |
ON malfunction (D)
|
Shift solenoid valve SR OFF malfunction |
Detected |
ON malfunction (E)
|
1-2 shift valve malfunction |
Detected |
ON malfunction (F)
|
Shift solenoid valve SL1 OFF malfunction |
Detected |
ON malfunction (G)
|
Shift solenoid valve SL2 ON malfunction |
Detected |
INSPECTION PROCEDURE
PROCEDURE
|
1. |
CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTCS P0894 AND P2714) |
(a) Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
(b) Turn the ignition switch ON and push the intelligent tester main switch ON.
(c) Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
(d) Read the DTCs using the intelligent tester.
|
Display (DTC output) |
Proceed to |
|---|---|
|
A |
|
P0894, P2714 and other DTCs are output |
B |
HINT:
If any other codes besides P0894 and P2714 are output, perform troubleshooting for those DTCs first.
| B |
|
|
|
2. |
PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SHIFT SOLENOID VALVE SLT) |
NOTICE:
- Perform the test at the normal operating ATF temperature: 50 to 80°C (122 to 176°F).
- Be careful to prevent SST's hose from interfering with the exhaust pipe.
- Perform the test with the A/C OFF.
HINT:
Performing the intelligent tester's ACTIVE TEST allows relay, VSV, actuator and other items to be operated without removing any parts. Performing the ACTIVE TEST early in troubleshooting is one way to save time. The DATA LIST can be displayed during the ACTIVE TEST.
(a) Remove the test plug on the transmission case center right side and connect SST.
SST: 09992-00095
09992-00231
09992-00271
(b) Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
|
(c) Start the engine and warm it up. |
|
(d) Measure the line pressure with SST.
(e) Turn the intelligent tester ON.
(f) Enter the following menus: DIAGNOSIS / OBD/MOBD / ECT / ACTIVE TEST.
(g) Follow the instructions on the tester and perform the ACTIVE TEST.
(h) Measure the line pressure with SST.
ECM
|
Tester Display |
Test Part |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
LINE PRESS UP* |
Operate the shift solenoid SLT and raise line pressure |
ON or OFF HINT:
|
[Vehicle Condition]
|
HINT:
*: LINE PRESS UP in the Active Test is performed to check the line pressure changes by connecting SST to the automatic transmission, which is used in the Hydraulic Test
![2007 MY LX470 [08/2006 - ]; A750F AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM: HYDRAULIC TEST](../../../../stylegraphics/info.gif "2007 MY LX470 [08/2006 - ]; A750F AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM: HYDRAULIC TEST")
as well. Please note that the pressure values in the Active Test and Hydraulic Test are different.
OK:
The line pressure changes as specified when performing the ACTIVE TEST.
| NG |
|
|
|
3. |
PERFORM ACTIVE TEST USING INTELLIGENT TESTER (RUNNING TEST) |
NOTICE:
This test should always be performed with at least 2 people.
(a) Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
(b)
Clear the DTC
.
(c) Enter the following menus: DIAGNOSIS / OBD/MOBD / ECT / ACTIVE TEST.
(d) Perform the ACTIVE TEST using the intelligent tester.
HINT:
While driving, the shift position can be forcibly changed with the intelligent tester.
ECM
|
Tester Display |
Test Part |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
SHIFT |
Operate shift solenoid valve and set each shift position by yourself |
|
Possible to check operation of shift solenoid valves [Vehicle Condition] 50 km/h (30 mph) or less |
HINT:
- This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.
- The 4th to 5th up-shift must be performed with the accelerator pedal released.
- The 5th to 4th down-shift 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) display on the intelligent tester.
(e) Compare the ECM gear shift command and the actual gear position.
|
ECM gear shift command |
1st |
2nd |
3rd |
4th |
5th |
Proceed to |
||
|---|---|---|---|---|---|---|---|---|
|
Actual gear position under malfunction |
Shift solenoid S1 |
Stuck ON |
1st |
2nd |
2nd |
1st |
N*1 |
A |
|
Stuck OFF |
4th |
3rd |
3rd |
4th |
5th |
|||
|
Shift solenoid S2 |
Stuck ON*2 |
2nd |
2nd |
3rd |
3rd |
N*1 |
B |
|
|
Stuck OFF*3 |
1st |
1st |
4th |
4th |
5th |
|||
|
Shift solenoid SL2 |
Stuck ON |
1st |
2nd |
3rd |
4th |
N*1 |
C |
|
|
Stuck OFF |
1st |
2nd |
3rd |
4th |
5th |
|||
|
Shift solenoid SR |
Stuck ON*4 |
1st |
2nd |
3rd |
4th |
5th |
D |
|
|
Stuck OFF*5 |
1st |
2nd |
3rd |
4th |
4th |
|||
HINT:
- *1: Neutral
- *2: When shift solenoid S2 is stuck ON, the vehicle cannot drive in reverse.
- *3: When shift solenoid S2 is stuck OFF, the 4th to 5th upshift will have a large shift shock. Also, the 5th to 4th down-shift will have time lag.
- *4: Stuck ON condition can be determined by checking if shift shock has increased excessively.
- *5: When shift solenoid SR is stuck OFF, moving the shift lever from N to D will cause a large shift shock.
- Gear shift can be determined by paying attention to changes in rpm.
OK:
Gear position changes in accordance with the tester command.
| OK |
|
| B |
|
| C |
|
| D |
|
|
|
4. |
INSPECT SHIFT SOLENOID VALVE S1 |
|
(a) Remove the shift solenoid valve S1. |
|
(b) Measure the resistance of the solenoid value.
Standard resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Shift solenoid S1 connector - Shift solenoid S1 body |
20°C (68°F) |
11 to 15 Ω |
(c) Connect the battery's positive (+) lead to the terminal of the solenoid connector, and the negative (-) lead to the solenoid body.
(d) Check the operating noise of the solenoid valve.
OK:
Solenoid makes operating noise.
| OK |
|
| NG |
|
|
5. |
INSPECT SHIFT SOLENOID VALVE S2 |
|
(a) Remove the shift solenoid valve S2. |
|
(b) Measure the resistance of the solenoid value.
Standard resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Shift solenoid S2 connector - Shift solenoid S2 body |
20°C (68°F) |
11 to 15 Ω |
(c) Connect the battery's positive (+) lead to the terminal of the solenoid connector, and the negative (-) lead to the solenoid body.
(d) Check the operating noise of the solenoid valve.
OK:
Solenoid makes operating noise.
| OK |
|
| NG |
|
|
6. |
INSPECT SHIFT SOLENOID VALVE SL2 |
|
(a) Remove the shift solenoid valve SL2. |
|
(b) Measure the resistance of the solenoid value.
Standard resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Terminal 1 of the shift solenoid valve SL2 - terminal 2 |
20°C (68°F) |
5.0 to 5.6 Ω |
(c) Connect the battery's positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector. Then check that the valve moves and makes an operating noise.
(d) Check the operating noise of the solenoid valve.
OK:
Solenoid makes operating noise.
| OK |
|
| NG |
|
|
7. |
INSPECT SHIFT SOLENOID VALVE SR |
|
(a) Remove the shift solenoid valve SR. |
|
(b) Measure the resistance of the solenoid value.
Standard resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Shift solenoid SR connector - Shift solenoid SR body |
20°C (68°F) |
11 to 15 Ω |
(c) Connect the battery's positive (+) lead to the terminal of the solenoid connector, and the negative (-) lead to the solenoid body.
(d) Check the operating noise of the solenoid valve.
OK:
Solenoid makes operating noise.
| NG |
|
|
|
8. |
INSPECT SHIFT SOLENOID VALVE SL1 |
|
(a) Remove the shift solenoid valve SL1. |
|
(b) Measure the resistance of the solenoid value.
Standard resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Terminal 1 of the shift solenoid valve SL1 - terminal 2 |
20°C (68°F) |
5.0 to 5.6 Ω |
(c) Connect the battery's positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector. Then check that the valve moves and makes an operating noise.
(d) Check the operating noise of the solenoid valve.
OK:
Solenoid makes operating noise.
| OK |
|
| NG |
|
|
9. |
INSPECT SHIFT SOLENOID VALVE SLT |
|
(a) Remove the shift solenoid valve SLT. |
|
(b) Measure the resistance of the solenoid value.
Standard resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Terminal 1 of the shift solenoid valve SLT - terminal 2 |
20°C (68°F) |
5.0 to 5.6 Ω |
(c) Connect the battery's positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector. Then check that the valve moves and makes an operating noise.
(d) Check the operating noise of the solenoid valve.
OK:
Solenoid makes operating noise.
| NG |
|
|
|
10. |
INSPECT TRANSMISSION VALVE BODY ASSEMBLY |
(a) Check the transmission valve body assembly.
OK:
There are no foreign objects on each valve.
| NG |
|
|
|
11. |
INSPECT TORQUE CONVERTER CLUTCH ASSEMBLY |
(a)
Check the torque converter clutch assembly
.
OK:
The torque converter clutch operates normally.
| NG |
|
| OK |
|
|
|