MECHANICAL SYSTEM TEST [JA5A-EL]
BME051701030204
Mechanical System Test Preparation
1. Engage the parking brake and use wheel chocks at the front and rear of the wheels.
2. Inspect the engine coolant level. (See COOLING SYSTEM SERVICE WARNINGS.) (See ENGINE COOLANT LEVEL INSPECTION.)
3. Inspect the engine oil level. (See ENGINE OIL LEVEL INSPECTION.)
4. Inspect the ATF levels. (See Automatic Transaxle Fluid (ATF) Level Inspection.)
5. Inspect the ignition timing. (See Ignition Timing Inspection.)
6. Inspect the idle speed. (See Idle Speed Inspection.)
Line Pressure Test
-
Note
-
• Line pressure cannot be measured on the JA5A-EL automatic transaxle. Measure the low clutch pressure in place of D, S, and L range line pressures. Measure the reverse clutch pressure in place of R position line pressure.
1. Engine idling.
-
(1) Perform mechanical system test preparation. (See Mechanical System Test Preparation.)
-
Warning
-
• Removing the square head plug when the ATF is hot can be dangerous. Hot ATF can come out of the opening and badly burn you. Before removing the square head plug, allow the ATF to cool.
-
(2) Remove the plug and O-ring as shown in the figure.

-
(3) Connect the SSTs (49 L019 014, 49 B019 901B, and 49 0378 400C) to the low clutch pressure inspection port (D, S, and L range line pressures) or reverse clutch pressure inspection port (R position line pressure).
-
(4) Start the engine and warm it up until the ATF reaches 60-70 °C {140-158 °F}.
-
(5) Shift the selector lever to D range.
-
(6) Read the line pressure at idle for the remaining ranges in the same manner.
-
• S range
-
• L range
-
• R range
ATF temperature
-
60-70 °C {140-158 °F}
-
Turn off all electrical loads
|
Position/Range
|
Line pressure (kPa {kgf/cm2, psi})
|
|
Idle
|
|
D, S
|
290-490 {3.0-5.0, 42-71}
|
|
L, R
|
550-750 {5.6-7.6, 80-109}
|
-
(7) Turn the engine off.
2. Engine stall speed.
-
Caution
-
• Perform the line pressure test at engine idling 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) Replace the SST (49 B019 901B) with the gauge of the SST (49 0378 400C).
-
(2) Start the engine.
-
Caution
-
• Do not maintain WOT in any gear range for more than 5 s or transaxle damage will occur.
-
(3) Firmly depress the brake pedal with the left foot, and then gradually depress the accelerator pedal to the floor (WOT) with the right.
-
(4) When the engine speed no longer increases, quickly read the line pressure and release the accelerator pedal.
-
(5) Shift the selector lever to N position and let the engine idle for 1 min or more to cool the ATF.
-
(6) Read the line pressure at the engine stall speed for the remaining ranges in the same manner.
-
• S range
-
• L range
-
• R range
ATF temperature
-
60-70 °C {140-158 °F}
-
Turn off all electrical loads
|
Position/Range
|
Line pressure (kPa {kgf/cm2, psi})
|
|
Stall
|
|
D, S
|
1,280-1,480 {13.1-15.1, 186-215}
|
|
L, R
|
1,550-1,750 {15.8-17.8, 225-254}
|
-
(7) Shift the selector lever to P position.
-
(8) Turn off the engine.
-
(9) Remove the SSTs and install a new square head plug and O-ring in the line pressure inspection port.
Tightening torque
-
4.91-9.80 N·m {50-100 kgf·cm, 43.4-86.7 in·lbf}
Evaluation of line pressure test
|
Condition
|
Possible cause
|
|
Idle
|
Below specification
|
Low pressure in all ranges
|
Worn oil pump
Poor operation of each solenoid
Fluid leaking from oil strainer, oil pump, pressure regulator valve, torque converter relief valve, and/or pressure relief valve
Pressure regulator valve or pilot valve sticking
Damaged pressure regulator valve spring or pilot valve spring
|
|
Low pressure in D range only
|
Fluid leaking from hydraulic circuit of low clutch
|
|
Low pressure in S and L ranges only
|
Fluid leaking from hydraulic circuit of low clutch and 2-4 brake
|
|
Low pressure in R position only
|
Fluid leaking from hydraulic circuit of reverse clutch
Fluid leaking from hydraulic circuit of low and reverse brake clutch
|
|
Above specification
|
High pressure in all ranges
|
Throttle position sensor out of adjustment
TFT sensor malfunction
Poor operation of shift solenoid
Pilot valve sticking
Pressure reducing valve or plug sticking
|
|
Stall
|
Below specification
|
Low pressure in all ranges
|
Throttle position sensor out of adjustment
Pressure control solenoid malfunction
Poor operation of shift solenoid
Pilot valve sticking
Pressure reducing valve or plug sticking
|
Stall Speed Test
-
Caution
-
• Perform the line pressure test at engine idling 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. Perform mechanical system test preparation. (See Mechanical System Test Preparation.)
2. Connect a tachometer.
3. Start the engine.
4. Shift the selector lever to D range.
-
Caution
-
• Do not maintain WOT in any gear range for more than 5 s or transaxle damage will occur.
-
• If engine speed recorded by the tachometer exceeds maximum specified rpm, release the accelerator pedal immediately. Clutch or band slippage is indicator.
5. Firmly depress the brake pedal with the left foot, and gently depress the accelerator pedal to the floor (WOT) with the right.
6. When the engine speed no longer increases, quickly read the engine speed and release the accelerator pedal.
7. Shift the selector the to N position and let the engine idle for 1 min or more to cool the ATF.
8. Perform stall tests for the remaining ranges and position in the same manner.
-
• R position
-
• S range
-
• L range
Engine stall speed
-
ATF temperature: 60-70 °C {140-158 °F}
-
Turn off all electrical loads
-
2,100-2,500 rpm
9. Turn off the engine.
Evaluation of stall test
|
Condition
|
Possible cause
|
|
Above specification
|
In all forward ranges and R position
|
Insufficient line pressure
Worm oil pump
Poor operation of low clutch
Poor adjustment or malfunction of TR switch
Oil leaking from oil pump, control valve, and/or transmission case
Pressure regulator valve or pilot valve sticking
|
|
In all forward ranges
|
Low clutch slippage
Low one-way clutch slippage
Reduction one-way clutch slippage
|
|
In R position
|
Low and reverse brake slippage
Reverse clutch slippage
Reduction brake slippage
|
|
Below specification
|
In all forward ranges and R position
|
Engine out of tune
One-way clutch slippage within torque converter
|
Time Lag Test
1. Perform mechanical system test preparation. (See Mechanical System Test Preparation.)
2. Start the engine.
3. Warm up the engine until the ATF temperature reaches 60-70°C {140-158°}. Shift the selector lever from N position to D range.
4. Use a stopwatch to measure the time it takes from shifting until engagement is felt. Take three measurements for each test and average the results using the following formula.
Formula
-
Average time lag = (Time 1 + Time 2 + Time 3) / 3
5. Perform the test for the following shifts in the same manner.
-
• N position→P position
Time lag
-
N position→D range ... approx. 0.5-1.0 s
-
N position→R position ... approx. 0.6- 1.1 s
Evaluation of time lag test
|
Condition
|
Possible Cause
|
|
Above specification
|
N→D shift
|
Insufficient line pressure in all forward ranges
Low clutch slippage
Low one-way clutch slippage
Reduction one-way clutch slippage
|
|
N→R shift
|
Insufficient line pressure in R position
Low and reverse brake slippage
Reverse clutch slippage
Reduction brake slippage
|