On Vehicle Inspection
MECHANICAL SYSTEM TEST [LA4A-EL]Mechanical System Test Preparation
1. Engage the parking brake and use wheel chocks at the front and rear of the wheels.
2. Check the engine coolant.
3. Check the engine oil.
4. Check the Automatic Transmission Fluid (ATF) levels.
5. Check the ignition timing.
6. Check the idle speed.
Line Pressure Test
This test measures line pressure as a means of checking the hydraulic components and inspecting for oil leakage.
WARNING: Removing the inspection port bolt when the ATF is hot can be dangerous. Hot ATF can come out of the opening and badly burn. Before removing the inspection port bolt, allow the ATF to cool.
CAUTION: Perform the Line Pressure Test at engine idle prior to performing the test at engine stall. If line pressure is low at idle do not perform the test at engine stall or further transaxle damage will occur.
1. Remove the inspection port bolt shown in the figure.
2. Connect the SSTs (49 UN01 128, 49 B019 901, and 49 B019 903) to the line pressure inspection port.
3. Start the engine.
4. While depressing the brake pedal move the shifter to each sector position and record line pressure at engine idle.
5. Compare pressure valves recorded to values specified in follows table.
6. Turn the engine off,
7. Replace the SST (49 B019 901) to the 49 B019 902.
CAUTION: If the accelerator pedal is pressed for longer than 5 seconds while the brake pedal is depressed, the transaxle could be damaged. Therefore, do steps 5 and 6 within 5 seconds of each other.
8. Start the engine.
9. Shift the selector lever to R position.
10. Firmly depress the foot brake with the left foot, and gently depress the accelerator pedal with the right foot.
11. When the engine speed no longer increases, record line pressure and release the accelerator.
12. Shift the selector to N position and let the engine idle for 1 minute or more to cool the ATF.
13. Perform stall tests for the remaining ranges in the same manner.
(1) D range
(2) 2 range
(3) 1 range
14. Compare results with line pressure specifications in table.
15. Shift the selector lever to P position.
16. Turn off the engine.
17. Install a new square head plug in the inspection port.
Tightening torque 22 - 26 Nm (2.3 - 2.6 kgf-cm, 16 - 19 ft. lbs.)
Evaluation Of Line Pressure Test
Stall Test
This test is performed to determine if there is slippage at the friction elements or malfunction of the hydraulic components.
1. Start the engine.
2. Shift the selector lever to D range.
CAUTION: If the accelerator pedal is depressed for longer than 5 seconds while the brake pedal is depressed, the transaxle could be damaged. Therefore, do steps 2 and 3 within 5 seconds of each other.
3. Firmly depress the brake pedal with the left foot, and then gradually depress the accelerator pedal with the right.
4. When the engine speed no longer increases, quickly read the engine speed and release the accelerator.
5. Shift the selector to N position and let the engine idle for 1 minute or more to cool the ATF.
6. Perform a stall test of R position in the same manner.
Engine stall speed 2,200 - 2,500 rpm
Evaluation Of Stall Test
7. Turn off the engine.
Time Lag Test
This test measures time lag as a means of checking the hydraulic components and the friction elements.
1. Start the engine.
2. Warm up the engine until the ATF reaches 66 - 77°C (150-170°F),
3. After normal operating temperature is reached, shift the selector from N position to D range.
4. Use a stopwatch to measure the time it takes from shifting until engagement is felt. Make three measurements for each test and average the results.
5. Perform the test for the following shifts in the same manner. 0 N position
- N position -> R position
Time lag
N -> D range...below approximately 1.0 second
N -> R position...below approximately 1.0 second
Evaluation Of Time Lag Test
6. Turn off the engine.
Torque Converter Clutch Operation Test
This test verifies that the torque converter clutch control system and the torque converter are operating properly.
WARNING: Doing this test by yourself can be dangerous. You could have an accident if you are looking at the manual or devices while driving, which may resulting in death or injury. Always have another person in the vehicle with you to read the manual or devices while you drive.
NOTE: Perform the OBD test. Check for a code P0741 or P0743. Refer to the appropriate pinpoint test or procedure for diagnosis.
1. Bring the engine to normal operating temperature by driving the vehicle at highway speeds for approximately 15 minutes in D range.
2. After normal operating temperature is reached, maintain a constant vehicle speed of about 80 km/h (50 mph), and tap the brake pedal with the left foot.
3. Engine rpm should increase when the brake pedal is tapped, and decrease about 5 seconds after the brake pedal is released. If this does not occur, refer to Torque Converter Operation Concern in Automatic Transaxle Symptom Troubleshooting [LA4A-EL].
4. If the vehicle stalls in D range at idle with the vehicle at a stop, move the selector lever to 1 range. If the vehicle stalls, the cause may be the converter control valve in the oil pump. Service as required. If the vehicle does not stall in 1 range, refer to Pinpoint Test C1 in Automatic Transaxle On-board Diagnosis [LA4A-EL].