AT-248
[EXC.F/EURO-OBD]
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
CAUTION:
If malfunction is detected in multiple systems including CAN communication line, CAN communication line trouble diagnosis
shall be performed first.Revolution sensor VHCL SPEED SEN·A/T
●TCM does not receive the proper voltage sig-
nal from the sensor.
Vehicle speed sensor
(Meter)VHCL SPEED SEN·MTR
●TCM does not receive the proper voltage sig-
nal from the sensor.
Accelerator pedal posi-
tion (APP) sensorTHROTTLE POSI SEN
●TCM receives an excessively low or high volt-
age from the sensor.
Shift solenoid valve A SHIFT SOLENOID/V A
●TCM detects an improper voltage drop when it
tries to operate the solenoid valve.
Shift solenoid valve B SHIFT SOLENOID/V B
●TCM detects an improper voltage drop when it
tries to operate the solenoid valve.
Overrun clutch solenoid
valveOVERRUN CLUTCH S/V
●TCM detects an improper voltage drop when it
tries to operate the solenoid valve.
T/C clutch solenoid valve T/C CLUTCH SOL/V
●TCM detects an improper voltage drop when it
tries to operate the solenoid valve.
A/T fluid temperature sen-
sorBATT/FLUID TEMP SEN
●TCM receives an excessively low or high volt-
age from the sensor.To be displayed in case
of abnormality and when
no recording is made.
Engine speed signal ENGINE SPEED SIG
●TCM does not receive the proper voltage sig-
nal from the ECM.
Line pressure solenoid
valveLINE PRESSURE S/V
●TCM detects an improper voltage drop when it
tries to operate the solenoid valve.
CAN communication CAN COMM CIRCUIT
●When malfunction is detected in CAN commu-
nication line.
TCM (RAM) CONTROL UNIT (RAM)
●TCM memory (RAM) is malfunctioningRefer to AT-351, "
TCM
TERMINALS AND REF-
ERENCE VALUE"
TCM (ROM) CONTROL UNIT (ROM)●TCM memory (ROM) is malfunctioningRefer to AT-351, "
TCM
TERMINALS AND REF-
ERENCE VALUE"
TCM (EEP ROM) CONT UNIT (EEP ROM)●TCM memory (EEP ROM) is malfunctioning.Refer to AT-351, "
TCM
TERMINALS AND REF-
ERENCE VALUE"
Detected items
(Screen terms for CONSULT-II, “SELF DIAGNOSIS”
test mode)Malfunction is detected when... Remarks
Item Display
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
AT-249
[EXC.F/EURO-OBD]
D
E
F
G
H
I
J
K
L
MA
B
AT
DATA MONITOR MODE (A/T)
Item Displaymove to center Monitor items
Description Remarks
TCM
Input
signalsCAN
comm
sig-
nalsMain
signalsSelection
from
menu
Vehicle speed
sensor 1 (A/T)
(Revolution sen-
sor)VHCL/S SE·A/T
[km/h] or [mph]
X——
●Vehicle speed com-
puted from signal of
revolution sensor is
displayed.When racing engine in N
or P with vehicle station-
ary, CONSULT-II data
may not indicate 0 km/h
(0 mph).
Vehicle speed
sensor 2
(Meter)VHCL/S
SE·MTR
[km/h] or [mph]
X——
●Vehicle speed com-
puted from signal of
vehicle speed sensor is
displayed.Vehicle speed display
may not be accurate
under approx. 10 km/h
(6 mph). It may not indi-
cate 0 km/h (0 mph)
when vehicle is station-
ary.
Accelerator pedal
position sensorTHRTL POS
SEN
[V]X——
●Accelerator pedal posi-
tion sensor signal volt-
age is displayed.
A/T fluid tempera-
ture sensorFLUID TEMP SE
[V]
X——
●A/T fluid temperature
sensor signal voltage is
displayed.
●Signal voltage lowers
as fluid temperature
rises.
Battery voltage BATTERY VOLT
[V]X——
●So urce vo ltage of TCM
is displayed.
Engine speed ENGINE SPEED
[rpm]
X—X
●Engine speed, com-
puted from engine
speed signal, is dis-
played.Engine speed display
may not be accurate
under approx. 800 rpm.
It m a y no t i ndi cat e 0 r p m
even when engine is not
running.
Overdrive control
switchOVERDRIVE
SW
[ON/OFF]X——
●ON/OFF state com-
puted from signal of
overdrive control SW is
displayed.
PN position (PNP)
switchPN POSI SW
[ON/OFF]
X——
●ON/OFF state com-
puted from signal of PN
position SW is dis-
played.
R position switch R POSITION SW
[ON/OFF]
X——
●ON/OFF state com-
puted from signal of R
position SW is dis-
played.
D position switch D POSITION SW
[ON/OFF]
X——
●ON/OFF state com-
puted from signal of D
position SW is dis-
played.
2 position switch 2 POSITION SW
[ON/OFF]
X——
●ON/OFF status, com-
puted from signal of 2
position SW, is dis-
played.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
AT-255
[EXC.F/EURO-OBD]
D
E
F
G
H
I
J
K
L
MA
B
AT
JUDGEMENT OF SELF-DIAGNOSIS CODE
O/D OFF indicator lamp:
All judgement flickers are the same.
All circuits that can be confirmed by self-diagnosis are OK.1st judgement flicker is longer than others.
Revolution sensor circuit is short-circuited or disconnected.
Go to VEHICLE SPEED SENSOR·A/T (REVOLUTION SEN-
SOR).
Refer to AT-353
2nd judgement flicker is longer than others.
Vehicle speed sensor circuit is short-circuited or disconnected.
Go to VEHICLE SPEED SENSOR·MTR.
Refer to AT- 3 5 83rd judgement flicker is longer than others.
Accelerator pedal position (APP) sensor circuit is short-circuited
or disconnected.
Go to ACCELERATOR PEDAL POSITION (APP) SENSOR.
Refer to AT-362
4th judgement flicker is longer than others.
Shift solenoid valve A circuit is short-circuited or disconnected.
Go to SHIFT SOLENOID VALVE A.
Refer to AT- 3 6 75th judgement flicker is longer than others.
Shift solenoid valve B circuit is short-circuited or disconnected.
Go to SHIFT SOLENOID VALVE B.
Refer to AT-372
SCIA0694ESCIA0695E
SCIA0696ESCIA0697E
SCIA0698ESCIA0699E
AT-256
[EXC.F/EURO-OBD]
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
6th judgement flicker is longer than others.
Overrun clutch solenoid valve circuit is short-circuited or discon-
nected.
Go to OVERRUN CLUTCH SOLENOID VALVE.
Refer to AT-3777th judgement flicker is longer than others.
Torque converter clutch solenoid valve circuit is short-circuited or
disconnected.
Go to TORQUE CONVERTER CLUTCH SOLENOID VALVE.
Refer to AT- 3 8 1
8th judgement flicker is longer than others.
A/T fluid temperature sensor is disconnected or TCM power
source circuit is damaged.
Go to BATT/FLUID TEMP SEN(A/T FLUID TEMP SENSOR
CIRCUIT AND TCM POWER SOURCE).
Refer to AT-3869th judgement flicker is longer than others.
Engine speed signal circuit is short-circuited or disconnected.
Go to ENGINE SPEED SIGNAL.
Refer to AT- 3 9 2
O/D OFF indicator lamp:
SCIA0700ESCIA0701E
SCIA0702ESCIA0703E
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]
D
E
F
G
H
I
J
K
L
MA
B
AT
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"
TROUBLE DIAGNOSIS — BASIC INSPECTION
AT-269
[EXC.F/EURO-OBD]
D
E
F
G
H
I
J
K
L
MA
B
AT
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