Land Cruiser URJ200 URJ202 GRJ200 VDJ200 - AB60F AUTOMATIC TRANSMISSION / TRANSAXLE
CHECK DTC OUTPUT (IN ADDITION TO DTC P0729)
PERFORM ACTIVE TEST USING INTELLIGENT TESTER (RUNNING TEST)
PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SHIFT SOLENOID VALVE SLT)
CLEAR DTC AND PERFORM RUNNING TEST
DTC P0729 Gear 6 Incorrect Ratio
DESCRIPTION
The ECM uses signals from the 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 or automatic transmission (clutch, brake or gear, etc.).
| DTC Code | DTC Detection Condition | Trouble Area |
| P0729 | A 6th gear shift malfunction: The ECM determines there is a malfunction when both of the following conditions are met (2 trip detection logic*1, 1 trip detection logic*2). (a) When the ECM directs the transmission to switch to 5th gear, the actual gear is also 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 up or stuck (sequence valve) Shift solenoid valve SLT remains open or closed Automatic transmission (clutch, brake or gear, etc.) |
- HINT:
| ECM gear shift command | 1st | 2nd | 3rd | 4th | 5th | 6th |
| Actual gear position under malfunction | 1st | 2nd | 3rd | 4th | 5th | 4th |
If any malfunction is detected, the ECM changes into the fail-safe mode to shift into the gear positions 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 |
MONITOR DESCRIPTION
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 DTC indicates that the sequence valve is locked in the direction the spring stretches and that shifting to the 6th gear is impossible.
INSPECTION PROCEDURE
| 1.CHECK DTC OUTPUT (IN ADDITION TO DTC P0729) |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Turn the intelligent tester on.
Enter the following menus: Powertrain / ECT / Trouble Codes.
Read the DTCs using the tester.
| Result | Proceed to |
| Only P0729 is output | A |
| P0729 and other DTCs are output | B |
- HINT:
- If any other codes besides P0729 are output, perform troubleshooting for those DTCs first.
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| A | |
| 2.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (RUNNING TEST) |
- CAUTION:
- This test should always be performed with at least 2 people.
- NOTICE:
- HINT:
- Using the intelligent tester 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.
Connect the intelligent tester to the DLC3.
Clear the DTC ().
Warm up the engine.
Enter the following menus: Powertrain / ECT / Active Test.
According to the display on the tester, perform the Active Test.
- HINT:
- While driving, the shift position can be forcibly changed with the intelligent tester.
- Comparing the shift position commanded by the Active Test with the actual shift position enables you to confirm the problem ().
| Tester Display | Test Part | Control Range | Diagnostic Note |
| Control the Shift Position | Operate shift solenoid valve and set each shift position | Press "→" button: Shift up Press "←" button: Shift down | It is possible to check the operation of the shift solenoid valves. [Vehicle Condition] The vehicle speed is 50 km/h (31 mph) or less. |
- HINT:
| Tester gear shift command | 1st | 2nd | 3rd | 4th | 5th | 6th |
| Actual gear position under malfunction | 1st | 2nd | 3rd | 4th | 5th | 4th |
- OK:
- Gear position changes in accordance with the tester command.
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| OK | |
| 3.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SHIFT SOLENOID VALVE SLT) |
- NOTICE:
- HINT:
- Using the intelligent tester 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 on the transmission case center right side and connect SST.
- SST
- 09992-00095(09992-00231,09992-00271)
Connect the intelligent tester to the DLC3.
Start the engine and warm it up.
Measure the line pressure with SST.
Turn the intelligent tester on.
Enter the following menus: Powertrain / ECT / Active Test.
According to the display on the tester, perform the Active Test.
Measure the line pressure.
| Tester Display | Test Part | Control Range | Diagnostic Note |
| Activate the Solenoid (SLT)* | Operate shift solenoid valve SLT and raise line pressure | ON or OFF
OFF: Line pressure up (when Active Test "Activate the Solenoid (SLT)" is performed, ECM commands shift solenoid valve SLT to turn OFF) ON: No action (normal operation) | [Vehicle Condition] The vehicle is stopped. The engine is idling. |
- HINT:
- *: Activate the Solenoid (SLT) 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 () as well. 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.
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| OK | |
| 4.CLEAR DTC AND PERFORM RUNNING TEST |
Clear the DTC ().
Check for DTC again after conducting the Monitor Drive Pattern ().
- OK:
- No DTC output
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| OK | ||
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