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CONTENTS
AUTOMATIC TRANSAXLE
SERVICE INFORMATION .. ..........................5
INDEX FOR DTC ............................................ .....5
Alphabetical Index ............................................... ......5
DTC No. Index .................................................... ......5
PRECAUTIONS .............................................. .....7
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
7
Precaution Necessary fo r Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
7
Precaution for On Board Diagnosis (OBD) System
of A/T and Engine ............................................... ......
8
Precaution ........................................................... ......8
Service Notice or Precaution ............................... ......9
PREPARATION .............................................. ....11
Special Service Tool ........................................... ....11
Commercial Service Tool .................................... ....14
A/T FLUID ....................................................... ....17
Checking A/T Fluid .............................................. ....17
Changing A/T Fluid ............................................. ....17
A/T Fluid Cooler Cleaning ................................... ....18
A/T CONTROL SYSTEM ................................ ....21
Cross-Sectional View ... ...........................................21
Shift Mechanism .................................................. ....22
TCM Function ...................................................... ....30
CAN Communication ........................................... ....31
Input/Output Signal of TCM ................................. ....31
Line Pressure Control .. ...........................................32
Shift Control ........................................................ ....33
Lock-up Control ................................................... ....34
Engine Brake Control (Ove rrun Clutch Control) ......35
Control Valve ....................................................... ....37
Centrifugal Cancel Mechanism ........................... ....37
ON BOARD DIAGNOSTIC (OBD) SYSTEM .. ....39
Introduction ......................................................... ....39
OBD-II Function for A/T System .......................... ....39 One or Two Trip Detection Logic of OBD-II .........
....39
OBD-II Diagnostic Trouble Code (DTC) .............. ....39
Malfunction Indicator Lamp (MIL) ............................41
TROUBLE DIAGNOSIS .................................... 42
DTC Inspection Priority Chart .............................. ....42
Fail-Safe .............................................................. ....42
How to Perform Trouble Diagnosis for Quick and
Accurate Repair ................................................... ....
43
A/T Electrical Parts Location ............................... ....49
Circuit Diagram .................................................... ....50
Inspections Before Trouble Diagnosis ................. ....51
Road Test ............................................................ ....55
Check Before Engine Is Started .......................... ....56
Check at Idle ........................................................ ....56
Cruise Test - Part 1 ............................................. ....58
Cruise Test - Part 2 ............................................. ....61
Cruise Test - Part 3 ............................................. ....62
Vehicle Speed at Which Gear Shifting Occurs .... ....64
Vehicle Speed at Which Lock-up Occurs/Releas-
es ......................................................................... ....
64
Symptom Chart .................................................... ....65
TCM Terminal and Refere nce Value .......................77
CONSULT-III Function (TRANSMISSION) .......... ....79
Diagnosis Procedure withou t CONSULT-III ............83
DTC U1000 CAN COMMUNICATION LINE ..... 88
Description ........................................................... ....88
On Board Diagnosis Logic ................................... ....88
Possible Cause .................................................... ....88
DTC Confirmation Procedure .............................. ....88
Wiring Diagram - AT - CAN ................................. ....89
Diagnosis Procedure ........................................... ....90
DTC P0705 PARK/NEUTRAL POSITION
(PNP) SWITCH .................................................. 91
Description ........................................................... ....91
CONSULT-III Reference Va lue in Data Monitor
Mode .................................................................... ....
91
On Board Diagnosis Logic ................................... ....91
Possible Cause .................................................... ....91

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SERVICE INFORMATION
INDEX FOR DTC
Alphabetical Index INFOID:0000000004305286
NOTE:
If DTC “CAN COMM CIRCUIT” is di splayed with other DTCs, first perform the trouble diagnosis for
DTC “CAN COMM CIRCUIT”. Refer to AT-88 .
*1: These numbers is prescribed by SAE J2012.
*2: When the fail-safe operation occurs, the MIL illuminates.
*3: The MIL illuminates when both the “Revolution sensor signal” and the “Vehicle speed sensor signal” meet the fail-safe condi tion at
the same time.
DTC No. Index INFOID:0000000004305287
NOTE:
If DTC “CAN COMM CIRCUIT” is di splayed with other DTCs, first perform the trouble diagnosis for
DTC “CAN COMM CIRCUIT”. Refer to AT-88 .
Items
(CONSULT-III screen terms) DTC
*1
Reference page
CONSULT-III or GST
A/T 1ST GR FNCTN P0731 AT-110A/T 2ND GR FNCTN P0732
AT-113A/T 3RD GR FNCTN P0733
AT-116A/T 4TH GR FNCTN P0734
AT-119A/T TCC S/V FNCTN P0744
AT-129ATF TEMP SEN/CIRC P0710
AT-96BATT/FLUID TEMP SEN —
AT-157CAN COMM CIRCUIT U1000
AT-88CONTROL UNIT (RAM) —
AT-168CONTROL UNIT (ROM) —
AT-168ENGINE SPEED SIG P0725
AT-106LINE PRESSURE S/V P0745
AT-134OVERRUN CLUTCH S/V P1760
AT-149PNP SW/CIRC P0705
AT-91SHIFT SOLENOID/V A*
2
P0750AT-139SHIFT SOLENOID/V B*
2
P0755AT-144T/C CLUTCH SOL/V P0740
AT-124TURBINE SENSOR —
AT-163VHCL SPEED SEN-A/T*
3
P0720AT-101VHCL SPEED SEN-MTR —
AT-154DTC
*1
Items
(CONSULT-III screen terms) Reference page
CONSULT-III or GST
P0705 PNP SW/CIRC AT-91P0710 ATF TEMP SEN/CIRC
AT-96P0720
VHCL SPEED SEN-A/T* 3
AT-101P0725 ENGINE SPEED SIG
AT-106P0731 A/T 1ST GR FNCTN
AT-110

P0733 A/T 3RD GR FNCTN
AT-116P0734 A/T 4TH GR FNCTN
AT-119P0740 T/C CLUTCH SOL/V
AT-124P0744 A/T TCC S/V FNCTN
AT-129P0745 LINE PRESSURE S/V
AT-134P0750
SHIFT SOLENOID/V A* 2
AT-139P0755
SHIFT SOLENOID/V B* 2
AT-144P1760 OVERRUN CLUTCH S/V
AT-149U1000 CAN COMM CIRCUIT
AT-88— BATT/FLUID TEMP SEN
AT-157— CONTROL UNIT (RAM)
AT-168— CONTROL UNIT (ROM)
AT-168— TURBINE SENSOR
AT-163— VHCL SPEED SEN-MTR
AT-154DTC
*1
Items
(CONSULT-III screen terms) Reference page
CONSULT-III or GST

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PREPARATION
Special Service Tool INFOID:0000000004305293
The actual shapes of Kent-Moore tools may differ fr om those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool name Description
ST2505S001
(J-34301)
Oil pressure gauge set
1. ST25051001 (J-34301)
Oil pressure gauge
2. ST25052000 (J-34301)
Hose
3. ST25053000
(J-25695-3)
Joint pipe
4. ST25054000
(J-25695-4)
Adapter
5. ST25055000
(J-25695-5)
Adapter Measuring line pressure
ST35325000
( — )
Drift Installing LH differential side oil seal
(Use with KV31103000)
a: 215 mm (8.46 in)
b: 25 mm (0.98 in) dia.
c: M12 X 1.5P
KV31103000
(J-38982)
Drift Installing LH differential side oil seal
(Use with ST35325000)
a: 59 mm (2.32 in) dia.
b: 49 mm (1.93 in) dia.
ST27180001
(J-25726-A)
Puller • Removing idler gear
• Removing output gear (HR16DE engine models)
a: 100 mm (3.94 in)
b: 110 mm (4.33 in)
c: M8 X 1.25P
KV31103200
(J-39186)
Clutch spring compressor • Removing and installing clutch spring retainer as-
sembly
• Removing and installing cancel cover
a: 179 mm (7.05 in)
b: 76 mm (2.99 in) dia.
c: 174 mm (6.85 in) SCIA7102E
NT424
SCIA7104E

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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.