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TM-20
< FUNCTION DIAGNOSIS >
A/T CONTROL SYSTEM
TCM Function
INFOID:0000000001603990
The function of the TCM is to:
• Receive input signals sent from various switches and sensors.
• Determine required line pressure, shifting poi nt, lock-up operation, and engine brake operation.
• Send required output signals to the respective solenoids.
CONTROL SYSTEM OUTLINE
The automatic transmission senses vehicle operating conditions through vari ous sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
1. Front brake 2. Input clutch3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch 9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
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SYSTEM SYMPTOMTM-171
< SYMPTOM DIAGNOSIS >
CEF
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TM
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56
Others Maximum speed low.
ON vehicle
1. Fluid level and state
TM-178
2. Line pressure testTM-187
3. Accelerator pedal position sensor TM-69
4. CAN communication line LAN-4
5. Direct clutch solenoid valveTM-84
6. Control valve with TCMTM-201
OFF vehicle7. Torque converter
TM-232
8. Oil pump assemblyTM-250
9. Input clutchTM-254
10. Gear systemTM-220
11. High and low reverse clutchTM-264
12. Direct clutchTM-266
13. Forward one- way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to
TM-8
, TM-9
TM-232
14 Forward brake (Parts behind drum support is impossible to
perform inspection by disassembly. Refer to TM-8
, TM-9TM-232
57 Extremely large creep. ON vehicle1. Engine idle speed
EC-172. CAN communication lineLAN-4
OFF vehicle 3. Torque converter TM-232
58With selector lever in
“P” position, vehicle
does not enter parking
condition or, with se-
lector lever in another
position, parking con-
dition is not cancelled.
Refer to
TM-119, "
In
"P" Position, Vehicle
Moves When
Pushed". ON vehicle
1. Transmission range switch
TM-43
2. Control cable adjustmentTM-194
OFF vehicle 3. Parking pawl components TM-220
59Vehicle runs with
transmission in “P” po-
sition. ON vehicle1. Transmission range switch
TM-43
2. Fluid level and stateTM-178
3. Control cable adjustmentTM-194
4. Control valve with TCMTM-201
5. Parking pawl componentsTM-220
OFF vehicle 6. Gear system TM-220
No. ItemsSymptom Condition Diagnostic ItemReference
page
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TM-178
< ON-VEHICLE MAINTENANCE >
A/T FLUID
ON-VEHICLE MAINTENANCE
A/T FLUID
Checking the A/T Fluid (ATF)INFOID:0000000004917424
CAUTION:
If using the vehicle for towing, the A/T fluid must be replaced as specified. Refer to MA-8, "
Introduc-
tion of Periodic Maintenance".
1. Before driving, the A/T fluid level can be checked at A/T fluid temperatures of 30 ° to 50° C (86° to 122° F) using the “COLD”
range on the A/T fluid level gauge as follows:
a. Park the vehicle on a level surface and set the parking brake.
b. Start the engine and move the shift selector through each gear position. Move the shift selector into the “P” position.
c. Check the A/T fluid level with the engine idling.
d. Remove the A/T fluid level gauge and wipe it clean with a lint- free paper.
CAUTION:
When wiping the A/T fluid from the A/ T fluid level gauge,
always use a lint-free paper, not a cloth.
e. Re-insert the A/T fluid level gauge into the A/T fluid charging pipe until the cap contacts the t op of the A/T fluid charging pipe
as shown.
CAUTION:
To check A/T fluid level, insert th e A/T fluid level gauge until
the cap contacts the top of the A/T fluid charging pipe, with
the gauge reversed from th e normal inserted position.
f. Remove the A/T fluid level gauge and note the A/T fluid level. If the A/T fluid level is at low si de of range, add A/T fluid to the
transmission through the A/T fluid charging pipe.
CAUTION:
Do not overfill the transmission with A/T fluid.
g. Install the A/T fluid level gauge and the A/T fluid level gauge bolt.
2. Warm up the engine and transmission.
3. Check for any A/T fluid leaks.
4. Drive the vehicle to increase the A/T fluid temperature to 80 ° C (176 ° F).
LLIA0071E
A/T fluid level
gauge bolt : Refer to
TM-214, "Removal and Installation (2WD)" or TM-216, "Removal
and Installation (4WD)"
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STALL TESTTM-185
< ON-VEHICLE MAINTENANCE >
CEF
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STALL TEST
Inspection and JudgmentINFOID:0000000001696156
A/T FLUID CHECK
Fluid Leakage and Fluid Level Check
• Inspect for fluid leakage and check the fluid level. Refer to TM-178, "Checking the A/T Fluid (ATF)".
Fluid Condition Check
Inspect the fluid condition.
STALL TEST
Stall Test Procedure
1. Inspect the amount of engine oil. Replenish the engine oil if necessary.
2. Drive for about 10 minutes to warm up the vehicle so that the A/
T fluid temperature is 50 to 80 °C (122 to 176 °F). Inspect the
amount of ATF. Replenish if necessary.
3. Securely engage the parking brake so that the tires do not turn.
Fluid condition Conceivable Cause Required Operation
Varnished (viscous
varnish state) Clutch, brake
scorchedReplace the ATF and check the A/T
main unit and the vehicle for mal-
functions (wire harnesses, cooler
pipes, etc.)
Milky white or
cloudy Water in the fluidReplace the ATF and check for plac-
es where water is getting in.
Large amount of
metal powder mixed
in Unusual wear of
sliding parts within
A/T
Replace the ATF and check for im-
proper operation of the A/T.
SAT638A
SAT647B
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LINE PRESSURE TESTTM-187
< ON-VEHICLE MAINTENANCE >
CEF
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LINE PRESSURE TEST
Inspection and JudgmentINFOID:0000000001696157
LINE PRESSURE TEST
Line Pressure Test Port
Line Pressure Test Procedure
1. Inspect the amount of engine oil and replenish if necessary.
2. Drive the car for about 10 minutes to warm it up so that the ATF reaches in range of 50 to 80 °C (122 to
176° F), then inspect the amount of ATF and replenish if necessary.
NOTE:
The automatic fluid temperature rises in range of 50 to 80 °C (122 to 176° F) during 10 minutes of
driving.
3. After warming up remove the oil pressure detection plug and install the Tool.
CAUTION:
When using the oil pressure ga uge, be sure to use the O-
ring attached to the oil pressure detection plug.
4. Securely engage the parking brake so that the tires do not turn.
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ROAD TESTTM-189
< ON-VEHICLE MAINTENANCE >
CEF
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ROAD TEST
DescriptionINFOID:0000000001696158
ROAD TEST
• The road test inspects overall performance of the A/T and analyzes possible malfunction causes.
• The road test is carried out in the following three stages.
1. Check before engine is started. Refer to TM-189
.
2. Check at idle. Refer to TM-189
.
3. Cruise test • Inspect all the items from Part 1 to Part 3. Refer to TM-190
, TM-192, TM-193.
• Before beginning the road test, check the test procedure and inspection items.
• Test all inspection items until the symptom is uncov ered. Diagnose NG items when all road tests are com-
plete.
Check Before Engine Is StartedINFOID:0000000001696159
1.CHECK AT CHECK INDICATOR LAMP
1. Park vehicle on level surface.
2. Move selector lever to “P” position.
3. Turn ignition switch to “OFF” position and wait at least 10 seconds.
4. Turn ignition switch to “ON” position. (Do not start engine.)
Does AT CHECK indicator lamp light up for about 2 seconds?
YES >> 1. Turn ignition switch to “OFF” position. 2. Carry out the self-diagnostics and record all NG items on the diagnostics worksheet. Refer toTM-32, "
CONSULT-III Function (TRANSMISSION)".
3. Go to TM-189, "
Check At Idle".
NO >> Stop the road test and go to TM-118, "
A/T Check Indicator Lamp Does Not Come On".
Check At IdleINFOID:0000000001696160
1.CHECK STARTING THE ENGINE
1. Park vehicle on level surface.
2. Move selector lever to “P” or “N” position.
3. Turn ignition switch to “OFF” position.
4. Turn ignition switch to “START” position.
Does the engine start?
YES >> GO TO 2.
NO >> Stop the road test and go to TM-118, "
Engine Cannot Be Started in "P" or "N" Position".
2.CHECK STARTING THE ENGINE
1. Turn ignition switch to “ON” position.
2. Move selector lever in “D”,“4”, “3”, “2”, “1” or “R” position.
3. Turn ignition switch to “START” position.
Does the engine start in either position?
YES >> Stop the road test and go to TM-118, "Engine Cannot Be Started in "P" or "N" Position".
NO >> GO TO 3.
3.CHECK “P” POSITION FUNCTIONS
1. Move selector lever to “P” position.
2. Turn ignition switch to “OFF” position.
3. Release the parking brake.
4. Push the vehicle forward or backward.
5. Engage the parking brake.
When you push the vehicle with disengaging the parking brake, does it move?
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TM-190
< ON-VEHICLE MAINTENANCE >
ROAD TEST
YES >> Enter a check mark at “In “P” Position Vehicle Moves When Pushed” on the diagnostics work-sheet, then continue the road test.
NO >> GO TO 4.
4.CHECK “N” POSITION FUNCTIONS
1. Start the engine.
2. Move selector lever to “N” position.
3. Release the parking brake.
Does vehicle move forward or backward?
YES >> Enter a check mark at “In “N” Position Vehicle Moves” on the diagnostics worksheet, then con- tinue the road test.
NO >> GO TO 5.
5.CHECK SHIFT SHOCK
1. Engage the brake.
2. Move selector lever to “D” position.
When the transmission is shifted from
“N” to “D”, is there an excessive shock?
YES >> Enter a check mark at “Large Shock ("N" to "D" Position) on the diagnostics worksheet, then con-
tinue the road test.
NO >> GO TO 6.
6.CHECK “R” POSITION FUNCTIONS
1. Engage the brake.
2. Move selector lever to “R” position.
3. Release the brake for 4 to 5 seconds.
Does the vehicle creep backward?
YES >> GO TO 7.
NO >> Enter a check mark at “Vehicle Does Not Creep Backward In "R" Position” on the diagnostics
worksheet, then continue the road test.
7.CHECK “D” POSITION FUNCTIONS
Inspect whether the vehicle creeps forward when the transmission is put into the “D” position.
Does the vehicle creep forward in the
“D” positions?
YES >> Go to TM-190, "Cruise Test - Part 1", TM-192, "Cruise Test - Part 2", and TM-193, "Cruise Test -
Part 3".
NO >> Enter a check mark at “Vehicle Does Not Cr eep Forward in "D" Position” on the diagnostics work-
sheet, then continue the road test.
Cruise Test - Part 1INFOID:0000000001696161
1.CHECK STARTING OUT FROM D1
1. Drive the vehicle for about 10 minutes to warm up the engine oil and ATF. Appropriate temperature for the ATF: 50 - 80° C (122 - 176°F)
2. Park the vehicle on a level surface.
3. Move selector lever to “P” position.
4. Start the engine.
5. Move selector lever to “D” position.
6. Press the accelerator pedal about half way down to accelerate the vehicle.
With CONSULT-III
Read off the gear positions.
Starts from D1?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle Cannot be St arted From D1” on the diagnostics worksheet, then
continue the road test.
2.CHECK SHIFT-UP D1 → D2
Press down the accelerator pedal about half way and inspect if the vehicle shifts up (D1 → D2) at the appropri-
ate speed.
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TM-246
< DISASSEMBLY AND ASSEMBLY >
DISASSEMBLY
59. Remove D-rings from reverse brake piston.
60. Knock out retaining pin using suitable tool.
61. Remove manual shaft retaining pin using suitable tool.
62. Remove manual plate (with parking rod) from manual shaft.
63. Remove parking rod from manual plate.
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