AUTOMATIC TRANSMISSION
SECTION
AT
CONTENTS
PREPARATION AND PRECAUTIONS............... 1003
Special Service Tools ...................................... 1003
Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº ... 1004
Precautions ...................................................... 1004
Service Notice or Precautions ......................... 1006
OVERALL SYSTEM............................................ 1007
A/T Electrical Parts Location ........................... 1007
Circuit Diagram ................................................ 1008
Wiring Diagram Ð A/T Ð ................................ 1009
Cross-sectional View ....................................... 1022
Hydraulic Control Circuits ................................ 1023
Shift Mechanism .............................................. 1024
Control System ................................................ 1026
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION..................................................... 1028
Self-diagnosis................................................... 1028
Diagnosis by CONSULT-II ............................... 1034
TROUBLE DIAGNOSIS Ð Introduction............ 1036
Introduction ...................................................... 1036
Diagnostic Worksheet ...................................... 1037
Work Flow ........................................................ 1040
TROUBLE DIAGNOSIS Ð Basic Inspection.... 1041
A/T Fluid Check ............................................... 1041
Stall Test .......................................................... 1041
Line Pressure Test........................................... 1044
Road Test ........................................................ 1046
TROUBLE DIAGNOSIS Ð General
Description.......................................................... 1057
Symptom Chart ................................................ 1057
TCM Terminals and Reference Value ............. 1060
TROUBLE DIAGNOSIS FOR VHCL SPEED
SENzA/T................................................................ 1064Vehicle Speed SensorzA/T (Revolution
sensor) ............................................................. 1064
TROUBLE DIAGNOSIS FOR VHCL SPEED
SENzMTR.............................................................. 1066
Vehicle Speed SensorzzMTR ............................ 1066
TROUBLE DIAGNOSIS FOR THROTTLE POSI
SEN...................................................................... 1068
Accelerator Position Sensor ............................ 1068
TROUBLE DIAGNOSIS FOR SHIFT
SOLENOID/V A.................................................... 1070
Shift Solenoid Valve A ..................................... 1070
TROUBLE DIAGNOSIS FOR SHIFT
SOLENOID/V B.................................................... 1072
Shift Solenoid Valve B ..................................... 1072
TROUBLE DIAGNOSIS FOR OVERRUN
CLUTCH S/V........................................................ 1074
Overrun Clutch Solenoid Valve ....................... 1074
TROUBLE DIAGNOSIS FOR T/C CLUTCH
SOL/V................................................................... 1076
Torque Converter Clutch Solenoid Valve ........ 1076
TROUBLE DIAGNOSIS FOR BATT/FLUID
TEMP SEN........................................................... 1079
A/T Fluid Temperature Sensor and TCM
Power Source .................................................. 1079
TROUBLE DIAGNOSIS FOR ENGINE SPEED
SIG....................................................................... 1082
Engine Speed Signal ....................................... 1082
TROUBLE DIAGNOSIS FOR LINE PRESSURE
S/V........................................................................ 1084
Line Pressure Solenoid Valve ......................... 1084
TROUBLE DIAGNOSIS FOR CONTROL UNIT
(RAM), CONTROL UNIT (ROM)......................... 1087
Description ....................................................... 1087
AT
+Extreme care should be taken to avoid damage to O-rings, seals and gaskets when assembling.
+After overhaul, refill the transmission 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
converter and ATF cooling system.
Always follow the procedures under ªChanging A/T Fluidº in the MA section when changing A/T fluid.
PREPARATION AND PRECAUTIONS
Precautions (Cont'd)
AT-1005
Control System
OUTLINE
The automatic transmission senses vehicle operating conditions through various sensors. It always controls
the optimum shaft position and reduces shifting and lock-up shocks.
SENSORSTCMACTUATORS
PNP switch
Accelerator position sensor
Accelerator position switch
(Full accel, off accel position
switch)
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Vehicle speed sensor
Overdrive control switch
A/T mode switch
c
Shift control
Line pressure control
Lock-up control
Overrun clutch control
Timing control
Fail-safe control
Self-diagnosis
Duet-EU control
CONSULT-II communication line
control
c
Shift solenoid valve A
Shift solenoid valve B
Overrun clutch solenoid valve
Torque converter clutch
solenoid valve
Line pressure solenoid valve
SPORT indicator lamp
CONTROL SYSTEM
SAT207K
OVERALL SYSTEM
AT-1026
TCM FUNCTION
The function of the TCM is to:
+Receive input signals sent from various switches and sensors.
+Determine required line pressure, shifting point, lock-up operation, and engine brake operation.
+Send required output signals to the respective solenoids.
INPUT/OUTPUT SIGNAL OF TCM
Sensors and solenoid valves Function
InputPNP switch Detects select lever position and sends a signal to TCM.
Accelerator position sensor Detects throttle valve position and sends a signal to TCM.
Accelerator position switch
(Off accel)Detects throttle valve's fully-closed position and sends a signal to TCM.
Accelerator position switch
(Full accel)Detects a throttle valve position of greater than 1/2 of full throttle and sends a
signal to TCM.
Engine speed signal From ECM.
A/T fluid temperature sensor Detects transmission fluid temperature and sends a signal to TCM.
Revolution sensor Detects output shaft rpm and sends a signal to TCM.
Vehicle speed sensorUsed as an auxiliary vehicle speed sensor. Sends a signal when revolution sen-
sor (installed on transmission) malfunctions.
Overdrive control switch
A/T mode switchSends a signal, which prohibits a shift to ªD
4º (overdrive) position, to the TCM.
OutputShift solenoid valve A/BSelects shifting point suited to driving conditions in relation to a signal sent from
TCM.
Line pressure solenoid valveRegulates (or decreases) line pressure suited to driving conditions in relation to
a signal sent from TCM.
Torque converter clutch solenoid valveRegulates (or decreases) lock-up pressure suited to driving conditions in relation
to a signal sent from TCM.
Overrun clutch solenoid valveControls an ªengine brakeº effect suited to driving conditions in relation to a sig-
nal sent from TCM.
O/D OFF indicator lamp
SPORT indicator lampShows TCM faults, when A/T control components malfunction.
OVERALL SYSTEM
Control System (Cont'd)
AT-1027
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
Symptom Chart
bON vehiclecbOFF vehiclec
Reference page (AT- )1041,
112611251064,
1066
108210441070,
11481072,
10841076,
10741079,
11241124 11241133,
11441161,
11651167,
11771167,
11751171,
11371184
Reference page (AT- )
Numbers are arranged in order of probability.
Perform inspections starting with number one
and work up. Circled numbers indicate that the
transmission must be removed from the
vehicle.
Fluid level
Control linkage
PNP switch
Accelerator position sensor (Adjustment)
Revolution sensor and vehicle speed sensor
Engine speed signal
Engine idling speed
Line pressure
Control valve assembly
Shift solenoid valve A
Shift solenoid valve B
Line pressure solenoid valve
Torque converter clutch solenoid valve
Overrun clutch solenoid valve
A/T fluid temperature sensor
Accumulator N-D
Accumulator 1-2
Accumulator 2-3
Accumulator 3-4 (N-R)
Ignition switch and starter
Torque converter
Oil pump
Reverse clutch
High clutch
Forward clutch
Forward one-way clutch
Overrun clutch
Low one-way clutch
Low & reverse brake
Brake band
Parking pawl components
1100 Engine does not start in ªNº, ªPº positions. . 2 3................1.......... .
1100 Engine starts in position other than ªNº and ªPº. . 1 2........................... .
Ð Transmission noise in ªPº and ªNº positions. 1 . . 3 45.2............
V7V6........ .
1100Vehicle moves when changing into ªPº position
or parking gear does not disengage when
shifted out of ªPº position..1............................
V2
1101 Vehicle runs in ªNº position. . 1................2...V4.V3.V5... .
1103Vehicle will not run in ªRº position (but runs in
ªDº, ª2º and ª1º positions). Clutch slips.
Very poor acceleration..1.....24..3..........
V5V6V7.V8.V9..
Ð Vehicle braked when shifting into ªRº position. 1 2.....35..4...........
V6V8.V9..V7.
Ð Sharp shock in shifting from ªNº to ªDº position. . .. 2 . 5137 . . 6 . . 48........
V10..... .
ÐVehicle will not run in ªDº and ª2º positions (but
runs in ª1º and ªRº position)..1.........................
V2.. .
1104Vehicle will not run in ªDº, ª1º and ª2º positions
(but runs in ªRº position). Clutch slips.
Very poor acceleration.1......24..3...5......
V6V7V8V9.V10.. .
Ð Clutches or brakes slip somewhat in starting. 12.3. . .46. .5. . .7. .8.
V13V12V10.V9...V11..
Ð Excessive creep.......1....................... .
1103 -
1104No creep at all. 1......23...........
V6V5..V4..... .
Ð Failure to change gear from ªD
1ºtoªD2º. .21.5...43...................V6.
Ð Failure to change gear from ªD
2ºtoªD3º. .21.5. . .4.3............V6.....V7.
Ð Failure to change gear from ªD
3ºtoªD4º. .21.4....3....5..............V6.
1106 -
1107,
1108Too high a gear change point from ªD
1ºtoªD2º,
from ªD2ºtoªD3º, from ªD3ºtoªD4º....12....34................... .
Ð Gear change directly from ªD
1ºtoªD3º occurs. 1...............2............V3.
ÐEngine stops when shifting lever into ªRº, ªDº,
ª2º and ª1º.......1.3. . .2.......
V4......... .
Ð Too sharp a shock in change from ªD
1ºtoªD2º....1...24.....5.3............V6.
Ð Too sharp a shock in change from ªD
2ºtoªD3º....1...24........3.....V5.....V6.
TROUBLE DIAGNOSIS Ð General Description
AT-1057
bON vehiclecbOFF vehiclec
Reference page (AT- )1041,
112611251064,
1066
108210441070,
11481072,
10841076,
10741079,
11241124 11241133,
11441161,
11651167,
11771167,
11751171,
11371184
Reference page (AT- )
Numbers are arranged in order of probability.
Perform inspections starting with number one
and work up. Circled numbers indicate that the
transmission must be removed from the
vehicle.
Fluid level
Control linkage
PNP switch
Throttle (accelerator) position sensor (Adjustment)
Revolution sensor and vehicle speed sensor
Engine speed signal
Engine idling speed
Line pressure
Control valve assembly
Shift solenoid valve A
Shift solenoid valve B
Line pressure solenoid valve
Torque converter clutch solenoid valve
Overrun clutch solenoid valve
A/T fluid temperature sensor
Accumulator N-D
Accumulator 1-2
Accumulator 2-3
Accumulator 3-4 (N-R)
Ignition switch and starter
Torque converter
Oil pump
Reverse clutch
High clutch
Forward clutch
Forward one-way clutch
Overrun clutch
Low one-way clutch
Low & reverse brake
Brake band
Parking pawl components
ÐToo sharp a shock in change from
ªD3ºtoªD4º....1...24.........3.......V6..V5.
ÐAlmost no shock or clutches slipping in change
from ªD
1ºtoªD2º.1..2...35.......4............V6.
ÐAlmost no shock or slipping in change from
ªD
2ºtoªD3º.1..2...35........4.....V6.....V7.
ÐAlmost no shock or slipping in change from
ªD
3ºtoªD4º.1..2...35.........4....V6.....V7.
ÐVehicle braked by gear change from ªD
1ºto
ªD2º.1.....................V2V4...V5V3..
ÐVehicle braked by gear change from ªD
2ºto
ªD3º.1............................V2.
ÐVehicle braked by gear change from ªD
3ºto
ªD4º.1.....................V4..V3V2... .
ÐMaximum speed not attained. Acceleration
poor.1.2.....534.........
V11V10V6V7....V9V8.
Ð Failure to change gear from ªD
4ºtoªD3º. 1..2....64.5.3............V8.V7..
ÐFailure to change gear from ªD
3ºtoªD2ºor
from ªD4ºtoªD2º.1..2....534............V6.....V7.
ÐFailure to change gear from ªD
2ºtoªD1ºor
from ªD3ºtoªD1º.1..2....534............V7...V6.V8.
ÐGear change shock felt during deceleration by
releasing accelerator pedal....1...24....3................ .
ÐToo high a change point from ªD
4ºtoªD3º, from
ªD3ºtoªD2º, from ªD2ºtoªD1º....12......................... .
ÐKickdown does not operate when depressing
pedal in ªD
4º within kickdown vehicle speed....12....34................... .
ÐKickdown operates or engine overruns when
depressing pedal in ªD
4º beyond kickdown
vehicle speed limit....21....34................... .
ÐRaces extremely fast or slips in changing from
ªD
4ºtoªD3º when depressing pedal.1..2...35..4...........V6V7..... .
ÐRaces extremely fast or slips in changing from
ªD
4ºtoªD2º when depressing pedal.1..2...365.4............V8....V7.
ÐRaces extremely fast or slips in changing from
ªD
3ºtoªD2º when depressing pedal.1..2...35..4..6..7.....V10V9....V8.
ÐRaces extremely fast or slips in changing from
ªD
4ºorªD3ºtoªD1º when depressing pedal.1..2...35..4............V6V7.V8.. .
Ð Vehicle will not run in any position. 1 2.....3...4........
V9V5.V6....V8V7V10
ÐTransmission noise in ªDº, ª2º, ª1º and ªRº
positions.1...................V2......... .
TROUBLE DIAGNOSIS Ð General Description
Symptom Chart (Cont'd)
AT-1058
bON vehiclecbOFF vehiclec
Reference page (AT- )1041,
112611251064,
1066
108210441070,
11481072,
10841076,
10741079,
11241124 11241133,
11441161,
11651167,
11771167,
11751171,
11371184
Reference page (AT- )
Numbers are arranged in order of probability.
Perform inspections starting with number one and
work up. Circled numbers indicate that the trans-
mission must be removed from the vehicle.
Fluid level
Control linkage
PNP switch
Throttle (accelerator) position sensor (Adjustment)
Revolution sensor and vehicle speed sensor
Engine speed signal
Engine idling speed
Line pressure
Control valve assembly
Shift solenoid valve A
Shift solenoid valve B
Line pressure solenoid valve
Torque converter clutch solenoid valve
Overrun clutch solenoid valve
A/T fluid temperature sensor
Accumulator N-D
Accumulator 1-2
Accumulator 2-3
Accumulator 3-4 (N-R)
Ignition switch and starter
Torque converter
Oil pump
Reverse clutch
High clutch
Forward clutch
Forward one-way clutch
Overrun clutch
Low one-way clutch
Low & reverse brake
Brake band
Parking pawl components
1111Failure to change from ªD3º to ª2º when changing
lever into ª2º position..712....654..3............V9..V8.
Ð Gear change from ª2
1ºtoª22º in ª2º position. . . 1........................... .
1112 Engine brake does not operate in ª1º position. .2134 . . . 65 . . . 7............
V8.V9..
Ð Gear change from ª1
1ºtoª12º in ª1º position. . 2 1........................... .
Ð Does not change from ª1
2ºtoª11º in ª1º position. ..1.2. . .43. . .5............V6.V7..
ÐLarge shock changing from ª1
2ºtoª11º in ª1º posi-
tion.........1...................V2..
Ð Transmission overheats. 1 . . 3 . . 2 4 6 . . 5........
V14V7V8V9V11.V12.V13V10.
ÐATF shoots out during operation.
White smoke emitted from exhaust pipe during
operation.1.....................
V2V3V5.V6.V7V4.
Ð Offensive smell at fluid charging pipe. 1...................
V2V3V4V5V7.V8.V9V6.
Ð Torque converter is not locked up. . .3124.68. . .7.5.....
V9......... .
Ð Torque converter clutch piston slip 1 . . 2 . . . 3 6 . . 5 4.......
V7......... .
1109 Lock-up point is extremely high or low. . . . 1 2 . . . 4 . . . 3................. .
ÐA/T does not shift to ªD
4º when driving with over-
drive control switch ªONº...213..864...57...........V10..V9.
ÐEngine is stopped at ªRº, ªDº, ª2º and ª1º posi-
tions.1.......543.2................. .
TROUBLE DIAGNOSIS Ð General Description
Symptom Chart (Cont'd)
AT-1059