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• The valve body contains precision parts and requires extreme care when parts are removed and serviced.
Place disassembled valve body parts in order for easier and proper assembly. Care will also prevent springs
and small parts from becoming scattered or lost.
• Properly installed valves, sleeves, plugs, etc. will slide along bores in valve body under their own weight.
• Before assembly, apply a coat of recommended ATF to all parts. Apply petroleum jelly to protect O-rings and
seals, or hold bearings and washers in pl ace during assembly. Do not use grease.
• Extreme care should be taken to avoid damage to O-rings, seals and gaskets when assembling.
• Clean or replace ATF cooler if excessive foreign material is found in oil pan or clogging strainer. Refer to AT-18, " A/T Fluid Cooler Cleaning " .
• After overhaul, refill the A/T with new ATF.
• When the A/T drain plug is removed, only some of the fluid is drained. Old A/T fluid will remain in torque con- verter and ATF cooling system.
Always follow the procedures under “Changing A/T Fluid” in the AT section when changing A/T fluid. Refer to
AT-17, " Changing A/T Fluid " ,
AT-17, " Checking A/T Fluid " .
Service Notice or Precaution INFOID:0000000004305292
ATF COOLER SERVICE If A/T fluid contains frictional material (clutches, bands, etc.), or if an A/T is repaired, overhauled, or replaced,
inspect and clean the A/T oil cooler mounted in the radiator or replace the radiator. Flush cooler lines using
cleaning solvent and compressed air after repair. Check Serv ice Bulletins for latest A/T oil cooler cleaning pro-
cedure. For radiator replacement, refer to CO-16, " Removal and Installation " (HR16DE engine models),
CO-38, " Removal and Installation " (MR18DE engine models).
TORQUE CONVERTER SERVICE The torque converter should be replaced under any of the following conditions:
• External leaks in the hub weld area.
• Converter hub is scored or damaged.
• Converter pilot is broken, damaged or fits poorly into crankshaft.
• Steel particles are found after flushing the cooler and cooler lines.
• Pump is damaged or steel particles are found in the converter.
• Vehicle has TCC shudder and/or no TCC apply. Replace only after all hydraulic and electrical diagnoses
have been made. (Converter clutch material may be glazed.)
• Converter is contaminated with engi ne coolant containing antifreeze.
• Internal malfunction of stator roller clutch.
• Heavy clutch debris due to overheating (blue converter).
• Steel particles or clutch lining material found in flui d filter or on magnet when no internal parts in unit are
worn or damaged — indicates that lining material came from converter.
The torque converter should not be replaced if:
• The fluid has an odor, is discolored, and there is no evidence of metal or clutch facing particles.
• The threads in one or more of the converter bolt holes are damaged.
• A/T malfunction did not display evidence of damaged or worn internal parts, steel particles or clutch plate lin-
ing material in unit and inside the fluid filter.
• Vehicle has been exposed to high mileage (only). The e xception may be where the torque converter clutch
dampener plate lining has seen excess wear by vehicles operated in heavy and/or constant traffic, such as
taxi, delivery or police use.
OBD-II SELF-DIAGNOSIS • A/T self-diagnosis is performed by the TCM in combination with the ECM. The results can be read through the blinking pattern of the OD OFF indicator lamp or the malfunction indicator lamp (MIL). Refer to the table
on AT-83, " Diagnosis Procedure without CONSULT-III " for the indicator used to display each self-diagnostic
result.
• The self-diagnostic results indicated by the MIL ar e automatically stored in both the ECM and TCM memo-
ries.
Always perform the procedure “HOW TO ERASE DTC” on AT-39, " OBD-II Diagnostic Trouble Code
(DTC) " to complete the repair and avo
id unnecessary blinking of the MIL.
• The following self-diagnostic items can be detected us ing ECM self-diagnostic results mode* only when the
OD OFF indicator lamp does not indicate any malfunctions.
- PNP switch
- A/T 1st, 2nd, 3rd, or 4th gear function
*: For details of OBD-II, refer to AT-39 .
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ST37830000
( — )
Drift Installing idler gear bearing outer race
a: 61.9 mm (2.437 in) dia.
b: 39 mm (1.54 in) dia.
ST33200000
(J-26082)
Drift Installing differential side bearings (HR16DE engine
models)
a: 60 mm (2.36 in) dia.
b: 44.5 mm (1.752 in) dia.
ST35271000
(J-26091)
Drift • Installing idler gear
• Installing output gear (HR16DE engine models)
a: 72 mm (2.83 in) dia.
b: 63 mm (2.48 in) dia.
ST3127S000
(J-25765-A)
Preload gauge
1. GG9103000
(J-25765-A)
Torque wrench
2. HT62940000
( — )
Socket adapter
3. HT62900000
( — )
Socket adapter • Measuring turning torque of reduction pinion gear
• Measuring turning torque of output shaft (HR16DE engine models)
• Measuring turning torque of final drive assembly
(MR18DE engine models)
KV38105710
(J-39026)
Preload adapter • Selecting differential side bearing adjusting shim
(MR18DE engine models)
• Measuring turning torque of final drive assembly (MR18DE engine models)
ST35321000
( — )
Drift Installing output shaft bearing (MR18DE engine mod-
els)
a: 49 mm (1.93 in) dia.
b: 41 mm (1.61 in) dia.
Tool number
(Kent-Moore No.)
Tool name DescriptionNT115
NT124
NT087
NT073
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A/T FLUID
Checking A/T Fluid INFOID:0000000004305295
1. Warm up engine.
2. Check for A/T fluid leakage.
3. Before driving, A/T fluid level can be checked at A/T fluid tem- peratures of 30 ° to 50 °C (86 ° to 122 °F) using the “COLD” range
on A/T fluid level gauge.
• A : Front side
• B : Reverse side
• C : Add
• D : OK
a. Park vehicle on level surface and set parking brake.
b. Start engine and move selector lever through each gear posi- tion. Leave selector lever in “P” position.
c. Check A/T fluid level with engine idling.
d. Remove A/T fluid level gauge and wipe clean with lint-free cloth. CAUTION:
When wiping the A/T fluid l evel gauge, always use lint-free
cloth.
e. Re-insert A/T fluid level gauge into A/T fluid charging pipe as far as it will go.
CAUTION:
Firmly fix the A/T fluid level ga uge to the A/T fluid charging
pipe using the stopper attached.
f. Remove A/T fluid level gauge and note reading. If reading is at low side of range, add A/T fluid to the A/T fluid charging pipe.
CAUTION:
Do not overfill.
4. Drive vehicle for approximately 5 minutes.
5. Re-check A/T fluid level at A/T fluid temperatures of 50° to 80 °C (122 ° to 176 °F) using “HOT” range on A/
T fluid level gauge.
CAUTION:
• When wiping the A/T fluid level gauge, always use lint-free cloth.
• Firmly fix the A/T fluid level ga uge to the A/T fluid charging pipe using the stopper attached.
6. Check A/T fluid condition and make any necessary repairs. Refer to AT-51, " Inspections Before Trouble
Diagnosis " . If the A/T fluid contains frictional material (clu
tches, bands, etc.), or if the A/T is repaired, over-
hauled, or replaced, inspect and clean the A/T fluid cooler mounted in the radiator. Refer to AT-18, " A/T
Fluid Cooler Cleaning " .
7. Install the removed A/T fluid level gauge into the A/T fluid charging pipe. CAUTION:
Firmly fix the A/T fluid level gaug e to the A/T fluid charging pipe using the stopper attached.
Changing A/T Fluid INFOID:0000000004305296
1. Warm up A/T fluid.
2. Stop engine.
3. Drain A/T fluid by removing the drain plug. Re install the drain plug to the specified torque.
CAUTION:
Do not reuse drain plug gasket.
4. Refill the transaxle with new specified A/T fluid th rough the A/T fluid charging pipe. Always refill the tran-
saxle with the same volume of A/T fluid that was drained out. B
Component " .
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FUNCTION OF CLUTCH AND BRAKE
CLUTCH AND BAND CHART 1. Torque converter 2. Oil pump 3. Input shaft
4. Brake band 5. Reverse clutch 6. High clutch
7. Front sun gear 8. Front pinion gear 9. Front internal gear
10. Front planetary carrier 11. Rear sun gear 12. Rear pinion gear
13. Rear internal gear 14. Rear planetary carrier 15. Forward clutch
16. Forward one-way clutch 17. Overrun clutch 18. Low one-way clutch
19. Low & reverse brake 20. Parking pawl 21. Parking gear
22. Output shaft 23. Idle gear 24. Output gear Shift posi-
tion R/C
5 H/C
6 F/C
15 O/C
17 Band servo
F/O.C
16 L/O.C
18 L&R/B
19 Lock-
up Remarks
2nd
apply 3rd re-
lease 4th ap-
ply
P PARK
POSITION
R REVERSE
POSITION
N NEUTRAL
POSITION
D*4 1st *1D B B
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The line pressure is temporarily reduced corresponding to a change
in engine torque when shifting gears (that is, when the shift solenoid
valve is switched for clutch operation) to reduce shifting shock.
AT LOW FLUID TEMPERATURE • A/T fluid viscosity and frictional characteristics of t he clutch facing change with A/T fluid temperature. Clutch
engaging or band-contacting pressure is compensated for, according to A/T fluid temperature, to stabilize
shifting quality.
• The line pressure is reduced below 60 °C (140 °F) to prevent shift-
ing shock due to high viscosity of A/T fluid when temperature is
low.
• Line pressure is increased to a maximum irrespective of the throt- tle opening when A/T fluid temperature drops to −10 °C (14 °F). This
pressure rise is adopted to prevent a delay in clutch and brake
operation due to extreme drop of A/T fluid viscosity at low temper-
ature.
Shift Control INFOID:0000000004305304
The shift is regulated entirely by electronic cont rol to accommodate vehicle speed and varying engine opera-
tions. This is accomplished by electrical signals trans mitted by the revolution sensor and the ECM (accelerator
pedal position sensor). This results in improved acceleration performance and fuel economy.
CONTROL OF SHIFT SOLENOID VALVES A AND B The TCM activates shift solenoid valves A and B according to sig-
nals from the accelerator pedal position sensor and revolution sen-
sor to select the optimum gear pos ition on the basis of the shift
schedule memorized in the TCM.
The shift solenoid valve performs simple ON-OFF operation. When
set to “ON”, the drain circuit closes and pilot pressure is applied to
the shift valve.
RELATION BETWEEN SHIFT SOLENOID VALVES A AND B AND GEAR POSITIONS SAT008J
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Lock-up Control System Diagram
Lock-up Released In the lock-up released state, the torque converter clutch control valve is set into the unlocked state by drain-
ing the torque converter clutch piston applying pressure and the torque converter clutch piston release pres-
sure is generated.
In this way, the torque converter clutch piston is not coupled.
Lock-up Applied In the lock-up applied state, the torque converter clutch control valve is set into the locked state by generating
the torque converter clutch piston applying pressure and t he torque converter clutch piston release pressure is
drained.
In this way, the torque converter clutch piston is pressed and coupled.
SMOOTH LOCK-UP CONTROL When shifting from the lock-up released state to the lock- up applied state, the current output to the torque con-
verter clutch solenoid is controlled with the TCM. In this way, when shifting to the lock-up applied state, the
torque converter clutch is temporarily set to the half-clutched state to reduce the shock.
Half-clutched State The current output from the TCM to the torque converte r clutch solenoid is varied to steadily increase the
torque converter clutch solenoid pressure.
In this way, the lock-up applying pressure gradually rises and while the torque converter clutch piston is put
into half-clutched status, the torque converter clutch piston applying pressure is increased and the coupling is
completed smoothly.
Engine Brake Control (Overrun Clutch Control) INFOID:0000000004305306
Forward one-way clutch is used to reduce shifting shoc ks in downshifting operations. This clutch transmits
engine torque to the wheels. However, drive force fr om the wheels is not transmitted to the engine because
the one-way clutch rotates idle. This means the engine brake is not effective.
The overrun clutch operates when the engine brake is needed.
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Control Valve
INFOID:0000000004305307
FUNCTION OF CONTROL VALVES
Centrifugal Cancel Mechanism INFOID:0000000004305308
FUNCTION The centrifugal cancel mechanism is a mechanism to c ancel the centrifugal hydraulic pressure instead of the
conventional check balls. It cancels the centrifugal hy draulic pressure which is generated as high clutch drum
rotates, and it allows for preventing high clutch from dragging and for providing stable high clutch piston press-
ing force in all revolution speeds.
STRUCTURE/OPERATION Valve name Function
Pressure regulator valve, plug and sleeve
plug Regulates oil discharged from the oil pump to provide optimum line pressure for all driving
conditions.
Pressure modifier valve and sleeve Used as a signal supplementary valve to the pressure regulator valve. Regulates pres- sure-modifier pressure (signal pressure) which controls optimum line pressure for all driv-
ing conditions.
Pilot valve Regulates line pressure to maintain a constant pilot pressure level which controls lock-up mechanism, overrun clutch, shift timing.
Accumulator control valve Regulates accumulator back-pressure to pressure suited to driving conditions.
Manual valve Directs line pressure to oil circuits corresponding to select positions. Hydraulic pressure drains when the shift lever is in Neutral.
Shift valve A Simultaneously switches three oil circuits using output pressure of shift solenoid valve A to meet driving conditions (vehicle speed, throttle opening, etc.).
Provides automatic downshifting and upshifting (1st → 2nd → 3rd → 4th gears/4th → 3rd
→ 2nd → 1st gears) in combination with shift valve B.
Shift valve B Simultaneously switches two oil circuits using output pressure of shift solenoid valve B in relation to driving conditions (vehicle speed, throttle opening, etc.).
Provides automatic downshifting and upshifting (1st → 2nd → 3rd → 4th gears/4th → 3rd
→ 2nd → 1st gears) in combination with shift valve A.
Overrun clutch control valve Switches hydraulic circuits to prevent engagement of the overrun clutch simultaneously with application of the brake band in D4. (Interlocking occurs if the overrun clutch engages
during D 4.)
1st reducing valve Reduces low & reverse brake pressure to dampen engine-brake shock when downshift- ing from the 1st position 12 to 1 1.
Overrun clutch reducing valve Reduces oil pressure directed to the overrun clutch and prevents engine-brake shock. In the 1st and 2nd positions, line pressure acts on the overrun clutch reducing valve to
increase the pressure-regulating point, with resultant engine brake capability.
Torque converter relief valve Prevents an excessive rise in torque converter pressure.
Torque converter clutch control valve, plug
and sleeve Activates or inactivates the lock-up function.
Also provides smooth lock-up through transient application and release of the lock-up
system.
1-2 accumulator valve and piston Lessens the shock find when the 2nd gear band servo contracts, and provides smooth shifting.
3-2 timing valve Switches the pace that oil pressure is released depending on vehicle speed; maximizes the high clutch release timing, and allows for soft downshifting.
Shuttle valve Determines if the overrun clutch solenoid valve should control the 3-2 timing valve or the overrun clutch control valve and switches between the two.
Cooler check valve At low speeds and with a small load when a little heat is generated, saves the volume of cooler flow, and stores the oil pressure for lock-up.