AT-250
[EXC.F/EURO-OBD]
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
1 position switch 1 POSITION SW
[ON/OFF]
X——●ON/OFF status, com-
puted from signal of 1
position SW, is dis-
played.
ASCD cruise sig-
nalASCD·CRUISE
[ON/OFF]
X——
●Status of ASCD cruise
signal is displayed.
ON... Cruising state
OFF... Normal running
state●This is displayed even
when no ASCD is
mounted.
ASCD OD cut sig-
nalASCD·OD CUT
[ON/OFF]
X——
●Status of ASCD OD
release signal is dis-
played.
ON... OD released
OFF... OD not released●This is displayed even
when no ASCD is
mounted.
Kickdown switch KICKDOWN SW
[ON/OFF]
X——
●ON/OFF status, com-
puted from signal of
kick down SW, is dis-
played.●This is displayed even
when no kick down
switch is equipped.
Closed throttle
position signalCLOSED THL/
SW
[ON/OFF]X——
●ON/OFF status, com-
puted from signal of
closed throttle position
signal, is displayed.●This means closed
throttle position signal
input via CAN com-
munication line.
Wide open throttle
position signalW/O THRL/P-
SW
[ON/OFF]
X——
●ON/OFF status, com-
puted from signal of
wide open throttle posi-
tion signal, is dis-
played.●This means wide
open throttle position
signal input via CAN
communication line.
Gear position GEAR
—— X
●Gear position data
used for computation
by TCM, is displayed.
Selector lever
positionSLCT LVR POSI
—— X
●Selector lever position
data, used for compu-
tation by TCM, is dis-
played.●A specific value used
for control is displayed
if fail-safe is activated
due to error.
Vehicle speed VEHICLE
SPEED
[km/h] or [mph]—— X
●Vehicle speed data,
used for computation
by TCM, is displayed.
Torque converter
slip ratioTC SLIP
RATIO
[0.000]———
●Ratio of engine revolu-
tion to input shaft revo-
lution of torque
converter
Torque converter
slip speedTC SLIP
SPEED
[rpm]———Difference in revolution
between input shaft revo-
lution and input shaft rev-
olution of torque
converterDisplay doesn't indicate
o rpm even if engine is
stopped.
But this isn't malfunc-
tion.
CAN communica-
tionCAN COMM
[OK/NG]—X—
CAN circuit 1CAN CIRC 1
[OK/UNKWN]—X—
CAN circuit 2CAN CIRC 2
[OK/UNKWN]—X— Item Displaymove to center Monitor items
Description Remarks
TCM
Input
signalsCAN
comm
sig-
nalsMain
signalsSelection
from
menu
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
AT-253
[EXC.F/EURO-OBD]
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Diagnostic Procedure Without CONSULT-IIECS004NX
SELF-DIAGNOSTIC PROCEDURE (WITHOUT CONSULT-II)
1.CHECK O/D OFF INDICATOR LAMP
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch to “OFF” position.
Wait 5 seconds.
3. Turn ignition switch to “ACC” position.
4. Set overdrive control switch to “ON” position.
5. Move selector lever to “P” position.
6. Turn ignition switch to “ON” position. (Do not start engine.)
7. Does O/D OFF indicator lamp come on for about 2 seconds?
Ye s o r N o
Ye s > > G O T O 2 .
No >> GO TO AT- 3 1 2 , "
O/D OFF Indicator Lamp Does Not
Come On" .
2.JUDGEMENT PROCEDURE STEP 1
1. Turn ignition switch to “OFF” position.
2. Turn ignition switch to “ACC” position.
3. Move selector lever to “D” position.
4. Set overdrive control switch to “OFF” position.
5. Turn ignition switch to “ON” position. (Do not start engine.)
Wait more than 2 seconds after turning ignition switch “ON”.
>> GO TO 3.
SAT774B
SCIA0693E
SAT653E
AT-258
[EXC.F/EURO-OBD]
TROUBLE DIAGNOSIS — INTRODUCTION
TROUBLE DIAGNOSIS — INTRODUCTION
PFP:00000
IntroductionECS004TF
The TCM receives a signal from the vehicle speed sensor, throttle
position sensor or PNP switch and provides shift control or lock-up
control via A/T solenoid valves.
Input and output signals must always be correct and stable in the
operation of the A/T system. The A/T system must be in good oper-
ating condition and be free of valve seizure, solenoid valve malfunc-
tion, etc.
It is much more difficult to diagnose a problem that occurs intermit-
tently rather than continuously. Most intermittent problems are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.
A visual check only, may not find the cause of the problems. A road
test with CONSULT-II or a circuit tester connected should be per-
formed. Follow the “Work Flow”. Refer to AT- 6 0
.
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a drive ability complaint. The cus-
tomer can supply good information about such problems, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “Diagnostic Worksheet” like the exam-
ple (AT- 5 7
) should be used.
Start your diagnosis by looking for “conventional” problems first. This
will help troubleshoot drive ability problems on an electronically con-
trolled engine vehicle.
Also check related Service bulletins for information.
SAT631IA
SAT632I
SEF234G
AT-260
[EXC.F/EURO-OBD]
TROUBLE DIAGNOSIS — INTRODUCTION
Diagnostic Worksheet
1.❏ Read the Fail-safe and listen to customer complaints.AT- 8 , "Wiring
Diagrams
and Trouble
Diagnosis",
AT-259,
"DIAGNOS-
TIC WORK-
SHEET"
2.❏ CHECK A/T FLUIDAT-264, "A/T
Fluid Check"❏ Leakage (Follow specified procedure)
❏ Fluid condition
❏ Fluid level
3.❏ Perform STALL TEST and LINE PRESSURE TEST.AT- 2 6 5 , "
Stall
Te s t",
AT-268, "
Line
Pressure
Te s t"
❏ Stall test — Mark possible damaged components/others.
❏ Torque converter one-way clutch
❏ Reverse clutch
❏ Forward clutch
❏ Overrun clutch
❏ Forward one-way clutch❏ Low & reverse brake
❏ Low one-way clutch
❏ Engine
❏ Line pressure is low
❏ Clutches and brakes except high clutch and
brake band are OK
❏ Line Pressure test — Suspected parts:
4.❏ Perform all ROAD TEST and mark required procedures.AT-269,
"Road Test"
4-1. Check before engine is started.AT-271, "1.
CHECK
BEFORE
ENGINE IS
STARTED"
❏ O/D OFF Indicator Lamp Does Not Come On, AT-312 .
❏ SELF-DIAGNOSTIC CONFIRMATION PROCEDURE — Mark detected items.
❏ Vehicle speed sensor·A/T (Revolution sensor), AT-353
.
❏ Vehicle speed sensor·MTR, AT- 3 5 8
.
❏ Accelerator pedal position (APP) sensor, AT-362
.
❏ Shift solenoid valve A, AT-367
.
❏ Shift solenoid valve B, AT-372
.
❏ Overrun clutch solenoid valve, AT-377
.
❏ Torque converter clutch solenoid valve, AT- 3 8 1
.
❏ A/T fluid temperature sensor and TCM power source, AT-386
.
❏ Engine speed signal, AT-392
.
❏ Line pressure solenoid valve, AT-396
.
❏ CAN communication line, AT-403
.
❏ Control unit (RAM), control unit (ROM), AT- 2 0 3 , "
DTC CONTROL UNIT (RAM), CONTROL UNIT
(ROM)" .
❏ Control unit (EEP ROM), AT- 2 0 5 , "
DTC CONTROL UNIT(EEPROM)" .
❏ PNP & overdrive control switches, and throttle position sensor, AT- 3 4 4
.
❏ Battery
❏ Others
4-2. Check at idleAT-272, "
2.
CHECK AT
IDLE"❏ Engine Cannot Be Started In “P” And “N” Position, AT-314 .
❏ In “P” Position, Vehicle Moves Forward Or Backward When Pushed, AT- 3 1 5
.
❏ In “N” Position, Vehicle Moves, AT- 3 1 5
.
❏ Large Shock. “N” → “R” Position, AT-317
.
❏ Vehicle Does Not Creep Backward In “R” Position, AT- 3 1 7
.
❏ Vehicle Does Not Creep Forward In “D”, “2” Or “1” Position, AT- 3 2 1
.
TROUBLE DIAGNOSIS — INTRODUCTION
AT-261
[EXC.F/EURO-OBD]
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4. 4-3. Cruise testAT- 2 7 5 , "3.
CRUISE
TEST",
AT- 2 7 9 ,
"Cruise Test
— Part 1"
Part-1
❏ Vehicle Cannot Be Started From D
1 , AT- 3 2 3 .
❏ A/T Does Not Shift: D
1→ D2 Or Does Not Kickdown: D4→ D2 , AT- 3 2 6 .
❏ A/T Does Not Shift: D
2→ D3 , AT-328 .
❏ A/T Does Not Shift: D
3→ D4 , AT-330 .
❏ A/T Does Not Perform Lock-up,AT- 3 3 2
.
❏ A/T Does Not Hold Lock-up Condition, AT-333
.
❏ Lock-up Is Not Released, AT-335
.
❏ Engine Speed Does Not Return To Idle (Light Braking D
4→ D3 ), AT- 3 3 6 .
Part-2AT- 2 8 2 ,
"Cruise Test
— Part 2"❏ Vehicle Does Not Start From D1 , AT-338 .
❏ A/T Does Not Shift: D
1→ D2 Or Does Not Kickdown: D4→ D2 , AT- 3 2 6 .
❏ A/T Does Not Shift: D
2→ D3 , AT-328 .
❏ A/T Does Not Shift: D
3→ D4 , AT-330 .
Part-3AT- 2 8 4 ,
"Cruise Test
— Part 3"❏ A/T Does Not Shift: D4→ D3 When Overdrive Control Switch “ON” → “OFF”, AT- 3 3 9 .
❏ Engine Speed Does Not Return To Idle (Engine Brake In D
3 ), AT-336 .
❏ A/T Does Not Shift: D
3→ 22 , When Selector Lever “D” → “2” Position, AT- 3 4 0 .
❏ Engine Speed Does Not Return To Idle (Engine Brake In 2
2 ),AT- 3 3 6 .
❏ A/T Does Not Shift: 2
2→ 11 , When Selector Lever “2” → “1” Position, AT- 3 4 1 .
❏ Vehicle Does Not Decelerate By Engine Brake, AT-343
.
❏ TCM Self-diagnosis Does Not Activate (PNP & Overdrive Control Switches, and throttle position sensor
Circuit Checks), AT- 3 4 4
.
❏ SELF-DIAGNOSTIC PROCEDURE — Mark detected items.
❏ Vehicle speed sensor·A/T (Revolution sensor), AT- 3 5 3
.
❏ Vehicle speed sensor·MTR, AT-358
.
❏ Accelerator pedal position (APP) sensor, AT-362
.
❏ Shift solenoid valve A, AT- 3 6 7
.
❏ Shift solenoid valve B, AT- 3 7 2
.
❏ Overrun clutch solenoid valve, AT- 3 7 7
.
❏ Torque converter clutch solenoid valve, AT-381
.
❏ Batt/fluid temp sen (A/T fluid temperature sensor and TCM power source), AT- 3 8 6
.
❏ Engine speed signal, AT- 3 9 2
.
❏ Line pressure solenoid valve, AT-396
.
❏ CAN communication line, AT- 4 0 3
.
❏ Control unit (RAM), control unit (ROM), AT-203, "
DTC CONTROL UNIT (RAM), CONTROL UNIT
(ROM)" .
❏ Control unit (EEP ROM), AT-205, "
DTC CONTROL UNIT(EEPROM)" .
❏ PNP & overdrive control switches, and throttle position sensor, AT- 3 4 4
.
❏ Battery
❏ Others
5.❏ For self-diagnosis NG items, inspect each component. Repair or replace the damaged parts.AT- 2 5 3 ,
"SELF-DIAG-
NOSTIC
PROCE-
DURE
(WITHOUT
CONSULT-
II)"
6.❏ Perform all ROAD TEST and re-mark required procedures.AT- 2 6 9 ,
"Road Test"
AT-266
[EXC.F/EURO-OBD]
TROUBLE DIAGNOSIS — BASIC INSPECTION
JUDGEMENT OF STALL TEST
The test result and possible damaged components relating to each result are shown in the illustrations on next
page.
In order to pinpoint the possible damaged components, follow the WORK FLOW shown in AT- 2 6 2 , "
Work
Flow" (EXCEPT FOR EURO-OBD).
NOTE:
Stall revolution is too high in “D”, “2” or “1” position:
●Slippage occurs in 1st gear but not in 2nd and 3rd gears...... Low one-way clutch slippage
●Slippage occurs in the following gears:
1st through 3rd gears in “D” position and engine brake functions with overdrive control switch set to
“OFF”.
1st and 2nd gears in “2” position and engine brake functions with accelerator pedal released (fully closed
throttle)...... Forward clutch or forward one-way clutch slippage
Stall revolution is too high in R position:
●Engine brake does not function in “1” position...... Low & reverse brake slippage
●Engine brake functions in “1” position...... Reverse clutch slippage
Stall revolution within specifications:
●Vehicle does not achieve speed of more than 80 km/h (50 MPH)...... One-way clutch seizure in torque
converter housing
CAUTION:
Be careful since automatic fluid temperature increases abnormally.
●Slippage occurs in 3rd and 4th gears in “D” position...... High clutch slippage
●Slippage occurs in 2nd and 4th gear in “D” position...... Brake band slippage
●Engine brake does not function in 2nd and 3rd gears in “D” position, 2nd gear in “2” position, and 1st gear
in “1” position with overdrive control switch set to “OFF”...... Overrun clutch slippage
Stall revolution less than specifications:
●Poor acceleration during starts...... One-way clutch slippage in torque converter
TROUBLE DIAGNOSIS — BASIC INSPECTION
AT-269
[EXC.F/EURO-OBD]
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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 AT-522, "
Line Pressure" .
JUDGEMENT OF LINE PRESSURE TEST
Road TestECS004VU
DESCRIPTION
●The purpose of the test is to determine overall performance of A/
T and analyze causes of problems.
●The road test consists of the following three parts:
1. Check before engine is started
2. Check at idle
SAT493G
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
●Fluid pressure leakage between oil strainer and pressure regulator valve
●Clogged strainer
Line pressure is low in particular posi-
tion.
●Fluid pressure leakage between manual valve and particular clutch
●For example, line pressure is:
− Low in “R” and “1” positions, but
− Normal in “D” and “2” positions.
Therefore, fluid leakage exists at or around low and reverse brake circuit.
Refer to AT-19, "
CLUTCH AND BAND CHART" .
Line pressure is high.
●Maladjustment 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.
●Maladjustment 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
SAT786A
TROUBLE DIAGNOSIS — BASIC INSPECTION
AT-271
[EXC.F/EURO-OBD]
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1. CHECK BEFORE ENGINE IS STARTED
1.CHECK O/D OFF INDICATOR LAMP
1. Park vehicle on flat surface.
2. Turn ignition switch to “OFF” position.
3. Move selector lever to “P” position.
4. Set overdrive control switch to “ON” position.
5. Turn ignition switch to “ON” position. (Do not start engine.)
6. Does O/D OFF indicator lamp come on for about 2 seconds?
Ye s o r N o
Ye s > > G O T O 2 .
No >> Stop ROAD TEST. GO TO AT- 3 1 2 , "
O/D OFF Indicator
Lamp Does Not Come On" .
2.CHECK O/D OFF INDICATOR LAMP
Does O/D OFF indicator lamp flicker for about 8 seconds?
Ye s o r N o
Yes (Except for Euro-OBD)>>TCM is under fail-safe mode. Per-
form self-diagnosis and check NG items on the DIAG-
NOSTIC WORKSHEET. Refer to AT- 2 5 9 ,
"DIAGNOSTIC WORKSHEET" and AT- 2 5 3 , "SELF-
DIAGNOSTIC PROCEDURE (WITHOUT CONSULT-II)"
.
No (Except for Euro-OBD)>>1.Turn ignition switch to “OFF” posi-
tion.
2. Perform self-diagnosis and note NG items.
Refer to AT- 2 5 3 , "
SELF-DIAGNOSTIC PROCEDURE
(WITHOUT CONSULT-II)" .
3. GO TO AT-272, "
2. CHECK AT IDLE" .
SAT774B
SCIA0693E
SCIA0693E