Page 857 of 1833

FON vehicleEFOFF vehicleE
Reference page (AT- )27,
120 11 9 56,
62,
82 30
65,
144 68,
86 71,
74 78,
11 8 11 8 11 8 71,
128 156,
160 162162,
170 166,
176 180
Numbers are arranged in order of probability.
Perform inspections starting with number one and
work up. Circled numbers indicate that the transmis-
sion must be removed from the vehicle.
Fluid level
Control linkage
Park/neutral position 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
Too sharp a shock in change from
ªD3ºtoªD4º. . ..1...24.........3. .
.....q6..q5.
Almost no shock or clutches slipping in change from
ªD
1ºtoªD2º. 1 ..2...35.......4... .
........q6.
Almost no shock or slipping in change from ªD
2ºto
ªD3º. 1 ..2...35........4.. ...
q6.....q7.
Almost no shock or slipping in change from ªD
3ºto
ªD4º. 1 ..2...35.........4. ...
q6.....q7.
Vehicle braked by gear change from ªD
1ºtoªD2º. 1 ................... .. q2q4...q5q3..
Vehicle braked by gear change from ªD
2ºtoªD3º. 1 ................... . ........q2.
Vehicle braked by gear change from ªD
3ºtoªD4º. 1 ................... .. q4..q3q2... .
Maximum speed not attained. Acceleration poor. 1 . 2 .....534.........q
11q10q6q7....q9q8.
Failure to change gear from ªD
4ºtoªD3º. 1 ..2....64.5.3...... . .....q8.q7..
Failure to change gear from ªD
3ºtoªD2º or from
ªD4ºtoªD2º. 1 ..2....534......... ...
q6.....q7.
Failure to change gear from ªD
2ºtoªD1º or from
ªD3ºtoªD1º. 1 ..2....534......... ...
q7...q6.q8.
Gear change shock felt during deceleration by
releasing accelerator pedal. . ..1...24....3...... .
......... .
Too high a change point from ªD
4ºtoªD3º, from ªD3º
to ªD2º, from ªD2ºtoªD1º. . ..12............... .
......... .
Kickdown does not operate when depressing pedal
in ªD
4º within kickdown vehicle speed. . ..12....34......... .
......... .
Kickdown operates or engine overruns when
depressing pedal in ªD
4º beyond kickdown vehicle
speed limit. . ..21....34......... .
......... .
Races extremely fast or slips in changing from ªD
4º
to ªD3º when depressing pedal. 1 ..2...35..4........ ...
q6q7..... .
Races extremely fast or slips in changing from ªD
4º
to ªD2º when depressing pedal. 1 ..2...365.4........ ....
q8....q7.
Races extremely fast or slips in changing from ªD
3º
to ªD2º when depressing pedal. 1 ..2...35..4..6..7.. ...
q10q9....q8.
Races extremely fast or slips in changing from ªD
4º
or ªD3ºtoªD1º when depressing pedal. 1 ..2...35..4........ ....
q6q7.q8.. .
Vehicle will not run in any position. 1 2 .....3...4........ q
9q5.q6.... q8q7q10
Transmission noise in ªDº, ª2º, ª1º and ªRº positions. 1
................... q2......... .
TROUBLE DIAGNOSIS Ð General Description
Symptom Chart (Cont'd)
AT-44
http://vnx.su/
Page 858 of 1833

FON vehicleEFOFF vehicleE
Reference page (AT- )27,
120 11 9 56,
62,
82 30
65,
144 68,
86 71,
74 78,
11 8 11 8 11 8 144,
128 156,
160 162162,
170 166,
176 180
Numbers are arranged in order of probability.
Perform inspections starting with number one and
work up. Circled numbers indicate that the transmis-
sion must be removed from the vehicle.
Fluid level
Control linkage
Park/neutral position 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
Failure to change from ªD3º to ª2º when changing
lever into ª2º position. . 712....654..3...... .
.....q9..q8.
Gear change from ª2
1ºtoª22º in ª2º position. . . 1 ................. . ......... .
Engine brake does not operate in ª1º position. . 2134 . . . 65 . . . 7...... ......q
8.q9..
Gear change from ª1
1ºtoª12º in ª1º position. . 2 1 ................. . ......... .
Does not change from ª1
2ºtoª11º in ª1º position. . . 1 . 2 . . . 4 3 . . . 5 ...... ......q6.q7..
Large shock changing from ª1
2ºtoª11º in ª1º posi-
tion. . .......1........... .
.......q2..
Transmission overheats. 1 . . 3 . . 2 4 6 . . 5 ........q
14q7q8q9q11.q12.q13q10.
ATF shoots out during operation.
White smoke emitted from exhaust pipe during
operation. 1 ................... ..
q
2q3q5.q6.q7q4.
Offensive smell at fluid charging pipe. 1 ................... q
2q3q4q5q7.q8.q9q6.
Torque converter is not locked up. . . 3124 . 68 . . . 7 . 5.....q
9......... .
Torque converter clutch piston slip 1 . . 2 . . . 3 6 . . 5 4 .......q
7......... .
Lock-up point is extremely high or low. . . . 1 2 . . . 4 . . . 3 ....... .......... .
A/T does not shift to ªD
4º when driving with over-
drive control switch ªONº. . .213..864...57..... .
.....q10..q9.
Engine is stopped at ªRº, ªDº, ª2º and ª1º positions. 1 .......543.2....... . ......... .
TROUBLE DIAGNOSIS Ð General Description
Symptom Chart (Cont'd)
AT-45
http://vnx.su/
Page 859 of 1833
TCM Terminals and Reference Value
PREPARATION
IMeasure voltage between each terminal and terminal q25orq48
by following ªTCM INSPECTION TABLEº.
TCM HARNESS CONNECTOR TERMINAL LAYOUT
TCM INSPECTION TABLE
(Data are reference values.)
Terminal No. Item Condition Judgement
standard
1 Line pressure solenoid
valve
When releasing accelerator pedal
after warming up engine. 1.5 - 3.0V
When depressing accelerator pedal
fully after warming up engine. 0.5V or less
2 Line pressure solenoid
valve
(with dropping resistor) When releasing accelerator pedal
after warming up engine.
4 - 14V
When depressing accelerator pedal
fully after warming up engine. 0.5V or less
3 Torque converter clutch
solenoid valve
When A/T performs lock-up. 8 - 15V
When A/T does not perform lock- up. Approximately 0V
5* DT1
ÐÐ
6* DT2 Ð Ð
7* DT3 Ð Ð
9* DT4 ÐÐ
ÐÐ
*: These terminals are connected to the ECM.
YAT412
YAT413
TROUBLE DIAGNOSIS Ð General Description
AT-46
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Page 860 of 1833

TerminalNo. Item Condition Judgement
standard
10 Power source
When turning ignition switch to ªONº. Battery voltage
When turning ignition switch to
ªOFFº. Approximately 0V
11 Shift solenoid valve A
When shift solenoid valve A oper-
ates.
(When driving in ªD
1ºorªD4º.) Battery voltage
When shift solenoid valve A does not
operate.
(When driving in ªD
2ºorªD3º.) Approximately 0V
12 Shift solenoid valve B When shift solenoid valve B oper-
ates.
(When driving in ªD
1ºorªD2º.)
Battery voltage
When shift solenoid valve B does
not operate.
(When driving in ªD
3ºorªD4º.) Approximately 0V
13 ªSPORTº indicator lamp
When setting A/T mode switch in
ªSPORTº position. Approximately 0V
When setting A/T mode switch in
other position. Battery voltage
16 Closed throttle position
switch
[in throttle (accelerator)
position switch] When releasing accelerator pedal
after warming up engine.
Battery voltage
When depressing accelerator pedal
after warming up engine. Approximately 0V
17 Wide open throttle posi-
tion switch
[in throttle (accelerator)
position switch] When depressing accelerator pedal
more than half-way after warming up
engine.
Battery voltage
When releasing accelerator pedal
after warming up engine. Approximately 0V
19 Power source Same as No. 104
20 Overrun clutch solenoid
valve
When overrun clutch solenoid valve
operates. Battery voltage
When overrun clutch solenoid valve
does not operate. Approximately 0V
22 Overdrive control switch
When setting overdrive control
switch in ªONº position Battery voltage
When setting overdrive control
switch in ªOFFº position 1V or less
25 Ground Ð Ð
26 Park/neutral ª1º position
switch When setting selector lever to ª1º
position.
Battery voltage
When setting selector lever to other
positions. Approximately 0V
27 Park/neutral ª2º position
switch When setting selector lever to ª2º
position.
Battery voltage
When setting selector lever to other
positions. Approximately 0V
28 Power source
(Back-up)
or
When turning ignition switch to
ªOFFº. Battery voltage
When turning ignition switch to ªONº. Battery voltage
TROUBLE DIAGNOSIS Ð General Description
TCM Terminals and Reference Value (Cont'd)
AT-47
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Page 861 of 1833

TerminalNo. Item Condition Judgement
standard
29 Revolution sensor
(Measure in AC rang)
When vehicle cruises at 30 km/h (19
MPH). 1V or more
Voltage rises gradually in
response to vehicle
speed.
When vehicle parks. 0V
30** Data link connector
ÐÐ
31** Data link connector Ð Ð
32 Throttle (accelerator)
position sensor
(Power source)
Ignition switch ON
4.5 - 5.5V
Ignition switch OFF 0.5 or less
34 Park/neutral ªDº position
switch When setting selector lever to ªDº
position.
Battery voltage
When setting selector lever to other
positions. Approximately 0V
35 Park/neutral ªRº position
switch When setting selector lever to ªRº
position.
Battery voltage
When setting selector lever to other
positions. Approximately 0V
36 Park/neutral ªNº or ªPº
position switch When setting selector lever to ªNº or
ªPº position.
Battery voltage
When setting selector lever to other
positions. Approximately 0V
39 Engine speed signal
When engine runs at idle speed. 0.8V
When engine runs at 2,000 rpm. Approximately 2.2V
40 Vehicle speed sensor
When moving vehicle at 2 to 3 km/h
(1 to 2 MPH) for1m(3ft)or more.Voltage varies between
less than 1V and more
than 4.5V
41 Throttle (accelerator)
position sensor
When depressing accelerator pedal
slowly after warming up engine.
(Voltage rises gradually in response
to throttle position.) 4.5 - 5.5V
42 Throttle (accelerator)
position sensor
(Ground) ÐÐ
43 SPORT indicator lamp
When setting A/T mode switch in
ªSPORTº position. Approximately 0V
When setting A/T mode switch in
other position. Battery voltage
44 A/T mode switch
ªSPORTº When setting A/T mode switch in
ªSPORTº position.
Battery voltage
When setting A/T mode switch in
other position. Approximately 0V
47 A/T fluid temperature
sensor When ATF temperature is 20ÉC
(68ÉF).
Approximately 1.5V
When ATF temperature is 80ÉC
(176ÉF). Approximately 0.5V
48 Ground Ð Ð
**: These terminals are connected to the data link connector.
TROUBLE DIAGNOSIS Ð General Description
TCM Terminals and Reference Value (Cont'd)
AT-48
http://vnx.su/
Page 862 of 1833
Wiring Diagram Ð AT Ð MAIN
YAT405
TROUBLE DIAGNOSIS FOR POWER SUPPLY
AT-49
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Page 863 of 1833
TCM Power Supply Circuit
DIAGNOSTIC PROCEDURE
CHECK TCM POWER SOURCE.
1. Turn ignition switch to ªONº position.(Do not start engine.)
2. Check voltage between TCM terminals q
10,q19and ground.
Battery voltage should exist.
OK
ENG Check the following items:
IHarness for short or
open between ignition
switch and TCM (Main
harness)
I Ignition switch and fuse
Refer to EL section
(ªPOWER SUPPLY
ROUTINGº).
CHECK TCM GROUND CIRCUIT.
1. Turn ignition switch to ªOFFº position.
2. Disconnect TCM harness connector.
3. Check resistance between TCM termi- nals q
25,q48and ground.
Resistance: Approximately 0W
If OK, check harness for short to
ground and short to power.
OK
ENG Repair open circuit or short
to ground or short to
power in harness or con-
nector.
INSPECTION END
YAT427
YAT428
H
H
TROUBLE DIAGNOSIS FOR POWER SUPPLY
AT-50
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Page 864 of 1833
Wiring Diagram Ð AT Ð VSSA/T
YAT400
TROUBLE DIAGNOSIS FOR VHCL SPEED SEN×A/T
AT-51
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