
AT-62
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Perform inspections starting with number one and work up.
Items Symptom Condition Diagnostic item Reference page
No Lock-up Engage-
ment/TCC InoperativeTorque converter is 
not locked up.ON vehicle1. Accelerator pedal position sensorEC-493
2. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
3. Engine speed signalAT- 1 0 1
4. A/T fluid temperature sensorAT- 9 1
5. Line pressure testAT- 4 8
6. Torque converter clutch solenoid valveAT- 11 9
7. Control valve assemblyAT- 2 1 6
OFF vehicle 8. Torque converterAT- 2 4 0
Torque converter 
clutch piston slip.ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. Torque converter clutch solenoid valveAT- 11 9
5. Line pressure solenoid valveAT- 1 2 9
6. Control valve assemblyAT- 2 1 6
OFF vehicle 7. Torque converterAT- 2 4 0
Lock-up point is ex-
tremely high or low.ON vehicle1. Accelerator pedal position sensorEC-4932. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
3. Torque converter clutch solenoid valveAT- 11 9
4. Control valve assemblyAT- 2 1 6
Shift ShockSharp shock in shift-
ing from “N” to “D” po-
sition.ON vehicle1. Engine idling speedEC-73
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. A/T fluid temperature sensorAT- 9 1
5. Engine speed signalAT- 1 0 1
6. Line pressure solenoid valveAT- 1 2 9
7. Control valve assemblyAT- 2 1 6
8. Accumulator N-DAT- 2 1 6
OFF vehicle 9. Forward clutchAT- 2 8 8
Too sharp a shock in 
changing from D
1  to 
D
2 .ON vehicle1. Accelerator pedal position sensorEC-493
2. Line pressure testAT- 4 8
3. Accumulator servo releaseAT- 2 1 6
4. Control valve assemblyAT- 2 1 6
5. A/T fluid temperature sensorAT- 9 1
OFF vehicle 6. Brake bandAT- 3 0 7 

TROUBLE DIAGNOSIS
AT-63
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
Shift ShockToo sharp a shock in 
changing from D
2  to 
D
3 .ON vehicle1. Accelerator pedal position sensorEC-493
2. Line pressure testAT- 4 8
3. Control valve assemblyAT- 2 1 6
OFF vehicle4. High clutchAT- 2 8 45. Brake bandAT- 3 0 7
Too sharp a shock in 
changing from D
3  to 
D
4 .ON vehicle1. Accelerator pedal position sensorEC-493
2. Line pressure testAT- 4 8
3. Control valve assemblyAT- 2 1 6
OFF vehicle4. Brake bandAT- 3 0 75. Overrun clutchAT- 2 8 8
6. Forward one-way clutchAT- 2 9 9
Gear change shock 
during deceleration by 
releasing accelerator 
pedal.ON vehicle1. Accelerator pedal position sensorEC-4932. Line pressure testAT- 4 8
3. Overrun clutch solenoid valveAT- 1 4 4
4. Control valve assemblyAT- 2 1 6
Large shock in chang-
ing from 1
2  to 11  in 
“1” position.ON vehicle 1. Control valve assemblyAT- 2 1 6OFF vehicle 2. Low & reverse brakeAT- 2 9 5
Improper Shift TimingToo high a gear 
change point from D
1  
to D
2 , from D2  to D3 , 
from D
3  to D4 .ON vehicle1. Accelerator pedal position sensorEC-493
2. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
3. Shift solenoid valve AAT- 1 3 4
4. Shift solenoid valve BAT- 1 3 9
Gear change directly 
from D
1  to D3  occurs.ON vehicle1. A/T fluid levelMA-222. Accumulator servo releaseAT- 2 1 6
OFF vehicle 3. Brake bandAT- 3 0 7
Too high a change 
point from D
4  to D3 , 
from D
3  to D 2 , from 
D
2  to D1 .ON vehicle1. Accelerator pedal position sensorEC-493
2. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
Kickdown does not 
operate when de-
pressing accelerator 
pedal in D
4  within 
kickdown vehicle 
speed.ON vehicle1. Accelerator pedal position sensorEC-493
2. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
3. Shift solenoid valve AAT- 1 3 4
4. Shift solenoid valve BAT- 1 3 9
Kickdown operates or 
engine overruns when 
depressing accelera-
tor pedal in D
4  be-
yond kickdown 
vehicle speed limit.ON vehicle1. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6
, AT- 1 4 9
2. Accelerator pedal position sensorEC-493
3. Shift solenoid valve AAT- 1 3 4
4. Shift solenoid valve BAT- 1 3 9
Gear change from 22  
to 2
3  in “2” position.ON vehicle1. PNP switch adjustmentAT- 2 1 92. Control cable adjustmentAT- 2 0 7
Gear change from 11  
to 1
2  in “1” position.ON vehicle1. PNP switch adjustmentAT- 2 1 92. Control cable adjustmentAT- 2 0 7
Items Symptom Condition Diagnostic item Reference page 

AT-64
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
No Down ShiftFailure to change 
gear from D
4  to D3 .ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Overrun clutch solenoid valveAT- 1 4 4
4. Shift solenoid valve A AT- 1 3 4
5. Line pressure solenoid valveAT- 1 2 9
6. Control valve assemblyAT- 2 1 6
OFF vehicle7. Brake bandAT- 3 0 78. Overrun clutchAT- 2 8 8
Failure to change 
gear from D
3  to D2  or 
from D
4  to D2 .ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Shift solenoid valve AAT- 1 3 4
4. Shift solenoid valve BAT- 1 3 9
5. Control valve assemblyAT- 2 1 6
OFF vehicle6. High clutchAT- 2 8 47. Brake bandAT- 3 0 7
Failure to change 
gear from D
2  to D1  or 
from D
3  to D1 .ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Shift solenoid valve AAT- 1 3 4
4. Shift solenoid valve BAT- 1 3 9
5. Control valve assemblyAT- 2 1 6
OFF vehicle6. Low one-way clutchAT- 2 4 07. High clutchAT- 2 8 4
8. Brake bandAT- 3 0 7
Failure to change 
from D
3  to 22  when 
shifting selector lever 
into “2” position.
AT- 1 9 4ON vehicle1. Accelerator pedal position sensorEC-4932. Shift solenoid valve BAT- 1 3 9
3. Control valve assembly AT- 2 1 6
4. Control cable adjustmentAT- 2 0 7
OFF vehicle 5. Brake bandAT- 3 0 7
Does not change from 
1
2  to 11  in 1st posi-
tion.ON vehicle1. PNP switch adjustmentAT- 2 1 9
2. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
3. Shift solenoid valve AAT- 1 3 4
4. Control valve assemblyAT- 2 1 6
5. Overrun clutch solenoid valveAT- 1 4 4
OFF vehicle6. Overrun clutchAT- 2 8 87. Low & reverse brakeAT- 2 9 5
Items Symptom Condition Diagnostic item Reference page 

TROUBLE DIAGNOSIS
AT-65
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
No Up ShiftFailure to change 
gear from D
1  to D2 .ON vehicle1. Control cable adjustmentAT- 2 0 7
2. Shift solenoid valve AAT- 1 3 4
3. Control valve assemblyAT- 2 1 6
4. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
5. Accelerator pedal position sensorEC-493
OFF vehicle 6. Brake bandAT- 3 0 7
Failure to change 
gear from D
2  to D3 .ON vehicle1. Control cable adjustmentAT- 2 0 7
2. Shift solenoid valve BAT- 1 3 9
3. Control valve assemblyAT- 2 1 6
4. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
5. Accelerator pedal position sensorEC-493
OFF vehicle6. High clutchAT- 2 8 47. Brake bandAT- 3 0 7
Failure to change 
gear from D
3  to D4 .ON vehicle 1. PNP switch adjustmentAT- 2 1 9
2. Overdrive control switchAT- 1 6 7
3. Control cable adjustmentAT- 2 0 7
4. Shift solenoid valve AAT- 1 3 4
5. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
6. A/T fluid temperature sensorAT- 9 1
OFF vehicle 7. Brake band AT- 3 0 7
A/T does not shift to 
D
4  when driving with 
OD ON. (OD OFF in-
dicator lamp is off.)ON vehicle1. Accelerator pedal position sensorEC-493
2. PNP switch adjustmentAT- 2 1 9
3. Overdrive control switchAT- 1 6 7
4. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
5. Shift solenoid valve AAT- 1 3 4
6. Overrun clutch solenoid valveAT- 1 4 4
7. Control valve assemblyAT- 2 1 6
8. A/T fluid temperature sensorAT- 9 1
9. Line pressure solenoid valveAT- 1 2 9
OFF vehicle10. Brake bandAT- 3 0 711. Overrun clutchAT- 2 8 8
Items Symptom Condition Diagnostic item Reference page 

AT-66
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Slips/Will Not EngageVehicle will not run in 
“R” position (but runs 
in “D”, “2” and “1” po-
sitions). Clutch slips.
Very poor accelera-
tion.ON vehicle1. Control cable adjustmentAT- 2 0 7
2. Stall testAT- 4 8
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
5. Control valve assemblyAT- 2 1 6
OFF vehicle6. Reverse clutchAT- 2 7 9
7. High clutchAT- 2 8 4
8. Forward clutchAT- 2 8 8
9. Overrun clutchAT- 2 8 8
10. Low & reverse brakeAT- 2 9 5
Vehicle will not run in 
“D” and “2” positions 
(but runs in “1” and 
“R” positions).ON vehicle 1. Control cable adjustmentAT- 2 0 7
OFF vehicle 2. Low one-way clutchAT- 2 4 0
Vehicle will not run in 
“D”, “1”, “2” positions 
(but runs in R posi-
tion). Clutch slips.
Very poor accelera-
tion.ON vehicle1. A/T fluid levelMA-22
2. Stall testAT- 4 8
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
5. Control valve assemblyAT- 2 1 6
6. Accumulator N-DAT- 2 1 6
OFF vehicle7. Reverse clutchAT- 2 7 9
8. High clutchAT- 2 8 4
9. Forward clutchAT- 2 8 8
10. Forward one-way clutchAT- 2 9 9
11. Low one-way clutchAT- 2 4 0
Clutches or brakes 
slip somewhat in start-
ing.ON vehicle1. A/T fluid levelMA-22
2. Control cable adjustmentAT- 2 0 7
3. Accelerator pedal position sensorEC-493
4. Line pressure testAT- 4 8
5. Line pressure solenoid valveAT- 1 2 9
6. Control valve assemblyAT- 2 1 6
7. Accumulator N-DAT- 2 1 6
OFF vehicle8. Forward clutchAT- 2 8 8
9. Reverse clutchAT- 2 7 9
10. Low & reverse brakeAT- 2 9 5
11 .  O i l  p u m pAT- 2 6 0
12. Torque converterAT- 2 4 0
Items Symptom Condition Diagnostic item Reference page 

TROUBLE DIAGNOSIS
AT-67
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
Slips/Will Not EngageNo creep at all.
AT- 1 8 1
, AT- 1 8 2
ON vehicle1. A/T fluid levelMA-222. Line pressure testAT- 4 8
3. Control valve assemblyAT- 2 1 6
OFF vehicle4. Forward clutchAT- 2 8 85. Oil pumpAT- 2 6 0
6. Torque converterAT- 2 4 0
Almost no shock or 
clutches slipping in 
change from D
1  to D2 
.ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. Accumulator servo releaseAT- 2 1 6
5. Control valve assemblyAT- 2 1 6
OFF vehicle 6. Brake bandAT- 3 0 7
Almost no shock or 
slipping in changing 
from D
2  to D3 .ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. Control valve assemblyAT- 2 1 6
OFF vehicle5. High clutchAT- 2 8 46. Forward clutchAT- 2 8 8
Almost no shock or 
slipping in changing 
from D
3  to D4 .ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. Control valve assemblyAT- 2 1 6
OFF vehicle 5. Brake bandAT- 3 0 7
Races extremely fast 
or slips in changing 
from D
4  to D3  when 
depressing accelera-
tor pedal.ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
5. Shift solenoid valve AAT- 1 3 4
6. Control valve assemblyAT- 2 1 6
OFF vehicle7. Brake bandAT- 3 0 78. Forward clutchAT- 2 8 8
Races extremely fast 
or slips in changing 
from D
4  to D2  when 
depressing accelera-
tor pedal.ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
5. Shift solenoid valve AAT- 1 3 4
6. Shift solenoid valve BAT- 1 3 9
7. Control valve assemblyAT- 2 1 6
OFF vehicle8. Brake bandAT- 3 0 79. Forward clutchAT- 2 8 8
Items Symptom Condition Diagnostic item Reference page 

AT-68
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Slips/Will Not EngageRaces extremely fast 
or slips in changing 
from D
3  to D2  when 
depressing accelera-
tor pedal. ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensor EC-493
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
5. Shift solenoid valve BAT- 1 3 9
6. Control valve assemblyAT- 2 1 6
OFF vehicle7. Brake bandAT- 3 0 78. High clutchAT- 2 8 4
Races extremely fast 
or slips in changing 
from D
4  or D3  to D 1  
when depressing ac-
celerator pedal.ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
5. Shift solenoid valve AAT- 1 3 4
6. Shift solenoid valve BAT- 1 3 9
7. Control valve assemblyAT- 2 1 6
OFF vehicle8. Forward clutchAT- 2 8 89. Forward one-way clutchAT- 2 9 9
10. Low one-way clutchAT- 2 4 0
Vehicle will not run in 
any position.ON vehicle1. A/T fluid levelMA-22
2. Control cable adjustmentAT- 2 0 7
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
OFF vehicle5. Oil pumpAT- 2 6 0
6. High clutchAT- 2 8 4
7. Brake bandAT- 3 0 7
8. Low & reverse brakeAT- 2 9 5
9. Torque converterAT- 2 4 0
10. Parking componentsAT- 2 3 0
OthersEngine cannot be 
started in “P” and “N” 
positions.
AT- 1 7 8
ON vehicle1. Ignition switch and starterPG-3
, SC-8
2. Control cable adjustmentAT- 2 0 7
3. PNP switch adjustmentAT- 2 1 9
Engine starts in posi-
tions other than “P” 
and “N”.ON vehicle1. Control cable adjustmentAT- 2 0 7
2. PNP switch adjustmentAT- 2 1 9
Transaxle noise in“ P” 
and “N” positions.ON vehicle1. A/T fluid levelMA-22
2. Line pressure testAT- 4 8
3. Accelerator pedal position sensorEC-493
4. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
OFF vehicle5. Oil pumpAT- 2 6 06. Torque converterAT- 2 4 0
Items Symptom Condition Diagnostic item Reference page 

AT-70
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
OthersMaximum speed not 
attained. Poor accel-
eration.ON vehicle1. A/T fluid levelMA-22
2. PNP switch adjustmentAT- 2 1 9
3. Overdrive control switchAT- 1 6 7
4. Accelerator pedal position sensorEC-493
5. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
6. Shift solenoid valve AAT- 1 3 4
7. Shift solenoid valve BAT- 1 3 9
8. Control valve assemblyAT- 2 1 6
OFF vehicle9. Reverse clutchAT- 2 7 9
10. High clutchAT- 2 8 4
11. Brake bandAT- 3 0 7
12. Low & reverse brakeAT- 2 9 5
13. Oil pumpAT- 2 6 0
14. Torque converterAT- 2 4 0
Transaxle noise in 
“D”, “2”, “1” and “R” 
positions.ON vehicle 1. A/T fluid levelMA-22
OFF vehicle 2. Torque converterAT- 2 4 0
Engine brake does 
not operate in “1” po-
sition.ON vehicle1. PNP switch adjustmentAT- 2 1 9
2. Control cable adjustmentAT- 2 0 7
3. Vehicle speed sensor·A/T (Revolution sensor) 
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
4. Control valve assemblyAT- 2 1 6
5. Overrun clutch solenoid valveAT- 1 4 4
OFF vehicle6. Overrun clutchAT- 2 8 87. Low & reverse brakeAT- 2 9 5
Transaxle overheats.ON vehicle1. A/T fluid levelMA-22
2. Engine idling speedEC-73 
3. Accelerator pedal position sensorEC-493
4. Line pressure testAT- 4 8
5. Line pressure solenoid valveAT- 1 2 9
6. Control valve assemblyAT- 2 1 6
OFF vehicle7. Oil pumpAT- 2 6 0
8. Reverse clutchAT- 2 7 9
9. High clutchAT- 2 8 4
10. Brake bandAT- 3 0 7
11. Forward clutchAT- 2 8 8
12. Overrun clutchAT- 2 8 8
13. Low & reverse brakeAT- 2 9 5
14. Torque converterAT- 2 4 0
Items Symptom Condition Diagnostic item Reference page