
Diagnostic Procedure....................................... 1088
TROUBLE DIAGNOSIS FOR CONTROL UNIT
(EFP ROM)........................................................... 1089
Description ....................................................... 1089
Diagnostic Procedure....................................... 1090
TROUBLE DIAGNOSIS FOR
NON-DETECTABLE ITEMS................................ 1091
PNP, Overdrive Control, A/T Mode or
Accelerator Position Switches ......................... 1091
DIAGNOSTIC PROCEDURES FOR
SYMPTOMS......................................................... 1097
1. SPORT Indicator Lamp Does Not
Come On.......................................................... 1097
2. SPORT Indicator Lamp Does Not
Come On.......................................................... 1098
3. O/D OFF Indicator Lamp Does Not Come
On .................................................................... 1098
4. SPORT Indicator Lamp Does Not
Come On.......................................................... 1099
5. Engine Cannot Be Started In ªPº and ªNº
Position ............................................................ 1100
6. In ªPº Position, Vehicle Moves Forward Or
Backward When Pushed ................................. 1100
7. In ªNº Position, Vehicle Moves .................... 1101
8. Large Shock. ªNº®ªRº Position ................ 1102
9. Vehicle Does Not Creep Backward In ªRº
Position ............................................................ 1103
10. Vehicle Does Not Creep Forward In ªDº,
ª2º Or ª1º Position ............................................ 1104
11. Vehicle Cannot Be Started From D
1......... 1105
12. A/T Does Not Shift: D
1®D2Or Does Not
Kickdown: D
4®D2......................................... 1106
13. A/T Does Not Shift: D
2®D3.................... 1107
14. A/T Does Not Shift: D
3®D4.................... 1108
15. A/T Does Not Perform Lock-up ................. 1109
16. A/T Does Not Hold Lock-up Condition ...... 1110
17. Lock-up Is Not Released ........................... 1110
18. Engine Speed Does Not Return To Idle
(Light Braking D
4®D3) .................................. 1111
19. Vehicle Does Not Start From D
1............... 1112
20. A/T Does Not Shift: D
2®D1When
Depressing Accelerator Pedal ......................... 1113
21. A/T Does Not Shift: D
4®D3, When
Overdrive Control Switch ªONº®ªOFFº ........ 1114
22. A/T Does Not Shift: D
3®22, When
Selector Lever ªDº®ª2º Position ................... 1114
23. A/T Does Not Shift: 2
2®11, WhenSelector Lever ª2º®ª1º Position .................... 1115
24. Vehicle Does Not Decelerate By Engine
Brake ................................................................ 1115
TROUBLE DIAGNOSES Ð A/T Shift Lock
System................................................................. 1116
Description ....................................................... 1116
Wiring Diagram Ð SHIFT Ð ........................... 1117
Diagnostic Procedure....................................... 1118
Key Interlock Cable.......................................... 1121
Component Check ........................................... 1122
ON-VEHICLE SERVICE...................................... 1124
Control Valve Assembly and Accumulators .... 1124
Revolution Sensor Replacement ..................... 1125
Rear Oil Seal Replacement ............................. 1125
Parking Pawl Components Inspection ............. 1125
PNP Switch Adjustment ................................... 1125
Manual Control Linkage Adjustment................ 1126
REMOVAL AND INSTALLATION....................... 1127
Removal ........................................................... 1127
Installation ........................................................ 1128
MAJOR OVERHAUL........................................... 1129
Oil Channel ...................................................... 1131
Locations of Needle Bearings, Thrust Washers
and Snap Rings ............................................... 1132
DISASSEMBLY.................................................... 1133
REPAIR FOR COMPONENT PARTS................. 1144
Oil Pump .......................................................... 1144
Control Valve Assembly................................... 1148
Control Valve Upper Body ............................... 1154
Control Valve Lower Body ............................... 1159
Reverse Clutch ................................................ 1161
High Clutch ...................................................... 1165
Forward and Overrun Clutches ....................... 1167
Low & Reverse Brake ...................................... 1171
Forward Clutch Drum Assembly ...................... 1175
Rear Internal Gear and Forward Clutch Hub .. 1177
Band Servo Piston Assembly .......................... 1180
Parking Pawl Components .............................. 1184
ASSEMBLY.......................................................... 1186
Assembly (1) .................................................... 1186
Adjustment ....................................................... 1190
Assembly (2) .................................................... 1195
A/T FLUID COOLER SYSTEM........................... 1205
A/T Fluid Cooler ............................................... 1205
SERVICE DATA AND SPECIFICATIONS (SDS)1206
General Specifications ..................................... 1206
Specifications and Adjustment......................... 1206
When you read wiring diagrams:
+Read GI section, ªHOW TO READ WIRING DIAGRAMSº.
+See EL section, ªPOWER SUPPLY ROUTINGº for power distribution circuit.
When you perform trouble diagnoses, read GI section, ªHOW TO FOLLOW FLOW
CHART IN TROUBLE DIAGNOSESº.
AT-1002

Special Service Tools
Tool number
Tool nameDescription
ST2505S001
Oil pressure gauge set
V1ST25051001
Oil pressure gauge
V2ST25052000
Hose
V3ST25053000
Joint pipe
V4ST25054000
Adapter
V5ST25055000
Adapter
NT097
Measuring line pressure
KV31101201
Oil pressure gauge
adapter
NT093
Measuring line pressure
ST07870000
Transmission case
stand
NT421
Disassembling and assembling
A/T
a: 182 mm (7.17 in)
b: 282 mm (11.10 in)
c: 230 mm (9.06 in)
d: 100 mm (3.94 in)
KV31102100
Torque converter one-
way clutch check tool
NT098
Checking one-way clutch in
torque converter
ST25850000
Sliding hammer
NT422
Removing oil pump assembly
a: 179 mm (7.05 in)
b: 70 mm (2.76 in)
c: 40 mm (1.57 in) dia.
d: M12 x 1.75P
ST33200000
Drift
NT091
Installing oil pump housing
oil seal
a: 60 mm (2.36 in) dia.
b: 44.5 mm (1.752 in) dia.
ST30720000
Drift
NT115
Installing rear oil seal
a: 77 mm (3.03 in) dia.
b: 55.5 mm (2.185 in) dia.
PREPARATION AND PRECAUTIONS
AT-1003

Shift Mechanism
The automatic transmission uses compact, dual planetary gear systems to improve power-transmission
efficiency, simplify construction and reduce weight.
It also employs an optimum shift control and superwide gear ratios. They improve starting performance and
acceleration during medium and high-speed operation.
Two one-way clutches are also employed: one is used for the forward clutch and the other for the low clutch.
These one-way clutches, combined with four accumulators, reduce shifting shock to a minimum.
CONSTRUCTION
V1Torque converter clutch piston
V2Torque converter
V3Oil pump
V4Input shaft
V5Brake band
V6Reverse clutch
V7High clutch
V8Front pinion gear
V9Front sun gear
V10Front internal gear
V11Front planetary carrier
V12Rear sun gear
V13Rear pinion gear
V14Rear internal gear
V15Rear planetary carrier
V16Forward clutch
V17Forward one-way clutch
V18Overrun clutch
V19Low one-way clutch
V20Low & reverse brake
V21Parking pawl
V22Parking gear
V23Output shaft
FUNCTION OF CLUTCH AND BRAKE
Control members Abbr. Function
V6Reverse clutch R/C To transmit input power to front sun gearV9.
V7High clutch H/C To transmit input power to front planetary carrierV11.
V16Forward clutch F/C To connect front planetary carrierV11with forward one-way clutchV17.
V18Overrun clutch O/C To connect front planetary carrierV11with rear internal gearV14.
V5Brake band B/B To lock front sun gearV9.
V17Forward one-way clutch F/O.CWhen forward clutch is engaged, to stop rear internal gearV14from rotating in oppo-
site direction.
V19Low one-way clutch L/O.C At D1position, to prevent rear internal gearV14from rotating in opposite direction.
V20Low & reverse brake L & R/BTo lock rear internal gearV14(2, 12and 11), to lock front planetary carrierV11(R
position).
SAT509I
OVERALL SYSTEM
AT-1024

CLUTCH AND BAND CHART
Shift positionV6
Reverse
clutchV7
High
clutchV16Forward
clutchV18Overrun
clutchBand servo
V17Forward
one-
way
clutchV19Low
one-
way
clutchV20Low &
reverse
brakeLock-up Remarks
2nd
apply3rd
release4th
apply
PPARK
POSITION
R
jjREVERSE
POSITION
NNEUTRAL
POSITION
D*41st
j*1jVX++
Automatic shift
1«2«3«4 2ndj*1jVj+
3rdjj*1jV*2^^+
4thj^*3^^jj
21stjjVX++Automatic shift
1«2
2nd
j*1jVj+
11stjj+jLocks (held sta-
tionary)
in 1st speed
1¬2 2nd
jjj+
*1: Operates when overdrive control or A/T mode switch is being set in ªOFFº or ªSPORTº position.
*2: Oil pressure is applied to both 2nd ªapplyº side and 3rd ªreleaseº side of band servo piston. However, brake band does not contract because oil
pressure area on the ªreleaseº side is greater than that on the ªapplyº side.
*3: Oil pressure is applied to 4th ªapplyº side in condition *2 above, and brake band contracts.
*4: A/T will not shift to 4th when overdrive control or A/T mode switch is set in ªOFFº or ªSPORTº position.
j: Operates
: Operates when throttle opening is less than 5.5/16, activating engine brake.
*: Operates during ªprogressiveº acceleration.
^: Operates but does not affect power transmission.
jVX: Operates when throttle opening is less than 5.5/16, but does not affect engine brake.
jV
OVERALL SYSTEM
Shift Mechanism (Cont'd)
AT-1025

A/T Fluid Check
FLUID LEAKAGE CHECK
1. Clean area suspected of leaking. Ð for example, mating
surface of converter housing and transmission case.
2. Start engine, apply foot brake, place selector lever in ªDº
position and wait a few minutes.
3. Stop engine.
4. Check for fresh leakage.
FLUID CONDITION CHECK
Fluid color Suspected problem
Dark or black with burned odor Wear of frictional material
Milky pinkWater contamination Ð Road water
entering through filler tube or breather
Varnished fluid, light to dark brown
and tackyOxidation Ð Over or under filling, Ð
Overheating
FLUID LEVEL CHECK
Refer to MA section (ªChecking A/T Fluidº, ªCHASSIS AND
BODY MAINTENANCEº).
Stall Test
STALL TEST PROCEDURE
1. Check A/T and engine fluid levels. If necessary, add.
2. Drive vehicle for approx. 10 minutes or until engine oil and
ATF reach operating temperature.
ATF operating temperature:
50 - 80ÉC (122 - 176ÉF)
3. Set parking brake and block wheels.
4. Install a tachometer where it can be seen by driver during
test.
+It is good practice to put a mark on point of specified
engine rpm on indicator.
5. Start engine, apply foot brake, and place selector lever in ªDº
position.
6. Accelerate to wide open throttle gradually while applying foot
brake.
7. Quickly note the engine stall revolution and immediately
release throttle.
+During test, never hold throttle wide open for more than
5 seconds.
Stall revolution:
2,480 - 2,680 rpm
SAT801A
SAT638A
SAT647B
SAT513G
SAT514G
TROUBLE DIAGNOSIS Ð Basic Inspection
AT-1041

Line Pressure Test
LINE PRESSURE TEST PORTS
+Location of line pressure test ports.
+Always replace line pressure plugs as they are self-seal-
ing bolts.
LINE PRESSURE TEST PROCEDURE
1. Check A/T and engine fluid levels. If necessary, add fluid.
2. Drive vehicle for approx. 10 minutes or until engine oil and
ATF reach operating temperature.
ATF operating temperature:
50 - 80ÉC (122 - 176ÉF)
3. Install pressure gauge to corresponding line pressure port.
SAT889HC
SAT647B
SAT890HC
SAT519GA
TROUBLE DIAGNOSIS Ð Basic Inspection
AT-1044

4. Set parking brake and block wheels.
+Continue to depress brake pedal fully while line pressure
test is being performed at stall speed.
5. Start engine and measure line pressure at idle and stall
speed.
+When measuring line pressure at stall speed, follow the
stall test procedure.
Line pressure:
Refer to SDS, AT-1207.
JUDGEMENT OF LINE PRESSURE TEST
Judgement Suspected parts
At idleLine pressure is low in all
positions.+Oil pump wear
+Control piston damage
+Pressure regulator valve or plug sticking
+Spring for pressure regulator valve damaged
+A/T fluid pressure leakage between oil strainer and pressure regulator valve
+Clogged strainer
Line pressure is low in par-
ticular position.+Fluid pressure leakage between manual valve and particular clutch
+For example, line pressure is:
Ð Low in ªRº and ª1º positions, but
Ð Normal in ªDº and ª2º positions.
Then, fluid leakage exists at or around low and reverse brake circuit.
Refer to ªCLUTCH AND BAND CHARTº, AT-1025.
Line pressure is high.+Mal-adjustment of throttle position sensor
+A/T fluid temperature sensor damaged
+Line pressure solenoid valve sticking
+Short circuit of line pressure solenoid valve circuit
+Pressure modifier valve sticking
+Pressure regulator valve or plug sticking
+Open in dropping resistor circuit
At stall speedLine pressure is low.+Mal-adjustment of throttle position sensor
+Line pressure solenoid valve sticking
+Short circuit of line pressure solenoid valve circuit
+Pressure regulator valve or plug sticking
+Pressure modifier valve sticking
+Pilot valve sticking
SAT513G
SAT493G
TROUBLE DIAGNOSIS Ð Basic Inspection
Line Pressure Test (Cont'd)
AT-1045

CRUISE TEST Ð Part 1
Drive vehicle for approx. 10 minutes to
warm engine oil and ATF up to operating
temperature.
ATF operating temperature:
50 - 80ÉC (122 - 176ÉF)
1. Park vehicle on flat surface.
2. Set overdrive control switch to ªONº
position.
3. Move selector lever to ªPº position.
4. Start engine.
Move selector lever to ªDº position.
Accelerate vehicle by constantly depress-
ing accelerator pedal halfway.
Does vehicle start from D1?
Read gear position.
Yes
cNo
Go to ª11. Vehicle Cannot
Be Started From D
1º,
AT-1105.
Does A/T shift from D1to D2at the speci-
fied speed?
Read gear position,
throttle opening and
vehicle speed.
Specified speed when shifting from
D
1to D2:
Refer to Shift schedule, AT-1206.
Yes
cNo
Go to ª12. A/T Does Not
Shift: D
1®D2Or Does
Not Kickdown: D
4®D2º,
AT-1106.
Does A/T shift from D2to D3at the speci-
fied speed?
Read gear position,
throttle position and
vehicle speed.
Specified speed when shifting from
D
2to D3:
Refer to Shift schedule, AT-1206.
Yes
cNo
Go to ª13. A/T Does Not
Shift: D
2®D3º, AT-1107.
VA
(Go to next page.)
SAT774B
SAT775B
SAT495G
SAT401H
.
.
.
.
.
.
.
TROUBLE DIAGNOSIS Ð Basic Inspection
Road Test (Cont'd)
AT-1053